3-(substituted methyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one derivatives useful as antitumor agents

ABSTRACT

The present invention is based on the discovery that certain 3-(substituted methyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one derivatives of formula I or a pharmaceutically acceptable salt thereof are useful as antitumor agents against sensitive and resistant tumor cells. ##STR1## Wherein X is NH or O, and R is defined in the specification.

The present invention relates to novel 3-(substitutedmethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one derivatives, and to thepreparation of such compounds, and to their incorporation inpharmaceutical compositions, and to their use as pharmacological agents,in particular for use in anti-cancer treatment.

BACKGROUND OF THE INVENTION

Since the invention of G0069A (JP 61-212587) and Tu 1718 (DE 3727651),we paid attention to develop β-lactam class of compounds as antitumoragents. However, there were a lot of difficulties to obtain thesecompounds in large scales. For example, only 20 mg of G0069A wasisolated from 10 L fermentation broth even after under well controlledfermentation techniques and suitable experimental conditions. On theother hand, another β-lactam compound having the same stereochemistry atC₅, (3R,5S)-3-hydroxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(clavam 1, G0069B) was isolated by Brown and Evans (J. Chem. Soc. Chem.Comm. 1979, 282) from the culture of Streptomyces clavuligerus, which isreported to exhibit antifungal activity. We have synthesized clavam 1and have done extensive biological evaluation. We found that clavam 1exhibit excellent antitumor activity both in vitro and in vivo but ischemically unstable. ##STR2##

The chemical unstability may be due to the intermolecular interaction of--OH to the β-lactam ring which results in the decomposition of product.

As a part of the program directed toward the development of β-lactamclass of compounds as novel antitumor agents, it is necessary to getcompounds which are relatively easy to synthesize, chemically stable andhave strong antitumor activity.

SUMMARY OF THE INVENTION

The present invention is based on the discovery that certain3-(substituted methyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one derivativesexhibit excellent activity against sensitive and resistant tumor cells.

In accordance to the present invention, there is provided a3-(substituted methyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one derivativeof general formula I or pharmaceutically acceptable salt thereof,##STR3## wherein X is NH or O, when X is NH,

R is hydrogen, --COR₁, wherein R₁ is (i) a C₁ -C₆ alkyl group which maybe substituted by 1-3 substituents selected from halogen, hydroxy,formyloxy, azido, carboxyl, heteroaryl or acetamide, (ii) a C₂ -C₄alkenyl group, (iii) a C₂ -C₄ alkynyl group, (iv) a C₃ -C₆ cycloalkylgroup, (v) a phenyl group which may be substituted by 1-3 substituentsselected from hydroxy, halogen, C₁ -C₆ alkoxy group or cyano, (vi) a C₅-C₆ heteroaryl group, (vii) a NR₂ R₃ wherein R₂ and R₃ are the same ordifferent and each is a hydrogen, C₁ -C₆ alkyl group or(7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl)methyl group or (viii)benzyloxy group;

--SO₂ R₄ wherein R₄ is a C₁ -C₆ alkyl group or a phenyl group which maybe substituted by 1-3 substituents selected from C₁ -C₆ alkyl group,halogen or C₁ -C₆ alkoxy group;

1-2 amino acid residue which may be substituted with protective group,

when X is O,

R is 1-2 amino acid residue which may be substituted with protectivegroup.

The pharmaceutically acceptable salts of formula I are selected fromsodium, potassium, magnesium, calcium, hydrogen chloride, tartaric acid,succinic acid, fumaric acid or p-toluenesulfonic acid.

Examples of C₁ -C₆ alkyl group as substitutents in R₁, R₂, R₃ or R₄ arestraight or branched chain alkyl group having 1-6 carbon atoms such asmethyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,tert-butyl, pentyl, 3-methylbutyl, hexyl and the like.

Examples of halogen atoms as substituents in R₁ or R₄ are fluorine,chlorine, bromine or iodine.

Examples of heteroaryl group in R₁ are 1,2,3-triazole, 1,2,4-triazole,thiophene, pyridine and the like.

Examples of C₂ -C₄ alkenyl group as defined in R₁ are alkenyl groupshaving 2-4 carbon atoms such as ethenyl, 1-propenyl, 2-propenyl,1-butenyl, 3-butenyl and the like.

Examples of C₂ -C₄ alkynyl group as defined in R₁ are ethynyl,1-propynyl, 2-propynyl, 1-butynyl, 3-butynyl and the like.

Examples of C₃ -C₆ cycloalkyl group as defined in R₁ are cyclopropyl,cyclobutyl, cyclopentyl, cyclohexyl and the like.

Examples of heteroaryl group or heteroaryl substituent in R₁ are C₅ -C₆heteroaryl group which may have 1-3 heteroatoms selected from nitrogenand sulfar such as 1,2,3-triazole, 1,2,4 triazole, thiophene, pyridineand the like.

Example of C₁ -C₆ alkoxy group as substituents in R₁ or R₄ are methoxy,ethoxy, propyloxy, butyloxy, pentyloxy, hexyloxy and the like.

The term "amino acid residue" used herein refers to the remaining groupafter the removal of the hydroxy group from a carboxy group of an aminoacid. The term "1-2 amino acid" used herein is one amino acid or onedipeptide constituted of two amino acids which are bonded each otherthrough a peptide bond.

Example of amino acid are α-amino acids which compose organisms proteinor their optical isomers such as glycine, D- or L-alanine, D- orL-valine, D- or L-leucine, D- or L-isoleucine, D- or L-serine, D- orL-threonine, D- or L-aspartic acid, D- or L-glutamic acid, D- orL-asparagine, D- or L-glutamine, D- or L-lysine, D- or L-arginine, D- orL-cysteine, D- or L-cystine, D- or L-methionine, D- or L-phenylalanine,D- or L-tyrosine, D- or L-tryptophane, D- or L-histidine, D- orL-proline and the like.

Examples of protective group in amino acid residue are benzyl and/oracyl group such as acetyl, 2-thienylacetyl, benzyloxycarbonyl,tert-butoxycarbonyl and the like.

Preferably, the derivatives of formula I wherein X is NH and R is --COR₁wherein R₁ is C₁ -C₆ alkyl group which may be substituted by 1-3substituents selected from halogen, hydroxy, formyloxy, azido, carboxy,heteroaryl or acetamido.

Preferably, the derivatives of formula I wherein X is NH and R is --COR₁wherein R₁ is a NR₂ R₃ wherein R₂ and R₃ are the same or different andeach is a hydrogen, C₁ -C₆ alkyl group or(7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl)methyl group.

Preferably, the derivatives of formula I wherein X is NH or O and R is1-2 amino acid residue which may be substituted with protective group.

Preferably, the derivative of formula I wherein X is NH, having (3R,5R)or (3S,5S) configuration at two asymmetric carbons on4-oxa-1-azabicyclo[3.2.0]heptan-7-one ring system or the mixture ofthem.

Preferably, the derivative of formula I wherein X is O, having (3R,5S)or (3S,5R) configuration at two asymmetric carbons on4-oxa-1-azabicyclo[3.2.0]heptan-7-one ring system or the mixture ofthem.

More specifically, when X is NH in general formula I, R is:

hydrogen

COR₁ wherein R₁ is selected from methyl, propyl, 1-methylethyl,chloromethyl, azidomethyl, (1,2,3-triazol-1-yl)methyl, formyloxymethyl,hydroxymethyl, trifluoromethyl, pentyl, 5-bromopentyl,5-formyloxypentyl, 5-azidopentyl, 5-(1,2,3-triazol-1-yl)pentyl,5-(acetamido)pentyl, cyclohexyl, 2-carboxyethyl, benzyloxy, phenyl,4-hydroxyphenyl, 4-methoxyphenyl, 3,4-dimethyoxyphenyl, 4-fluorophenyl,2,5-difluorophenyl, 2,4,5-trifluorophenyl, 4-cyanophenyl,thiophen-2-yl-methyl, pyridin-3-yl, diethylamino,(7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl)methylamino, 3-butenyl,ethynyl, aminomethyl, N-acetylaminomethyl,N-(L-2-N-benzyloxycarbonylamino-3-methylbutyryl)aminomethyl,N-(L-2-amino-3-methylbutyryl)aminomethyl,N-(L-2-N-benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)aminomethyl,N-(L-2-amino-3-carboxypropanoyl)aminomethyl,N-(D-4-N-benzyloxycarbonylamino-4-benzyloxycarbonylbutyryl)aminomethyl,N-(D-4-amino-4-carboxybutyryl)aminomethyl,L-1-N-benzyloxycarbonylaminoethyl, L-1-aminoethyl,D-1-N-benzyloxycarbonylaminoethyl, D-1-aminoethyl,L-1-N-benzyloxycarbonylamino-2-methylpropyl, L-1-amino-2-methylpropyl,D-1-N-benzyloxycarbonylamino-2-methylpropyl, D-1-amino-2-methylpropyl),L-1-N-benzyloxycarbonylamino-2-phnylethyl, L-1-amino-2-phenylethyl,L-1-N-benzyloxycarbonylamino-2-phenylethyl,L-1-N-(L-2-N-benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)amino-2-phenylethyl,L-1-N-(L-2-amino-3-carboxypropanoyl)amino-2-phenylethyl,L-1-N-benzyloxycarbonylamino-2-benzyloxycarbonylethyl,L-1-amino-2-carboxyethyl,D-3-N-benzyloxycarbonylamino-3-benzyloxycarbonylpropyl,D-1-amino-3-carboxypropyl, L-3-N-benzyloxycarbonylamino-2-hydroxyethylor L-1-amino-2-hydroxyethyl.

SO₂ R₄ wherein R₄ is selected from methyl, 4-methylphenyl,4-chlorophenyl or 4-methoxyphenyl group.

When X is O in general formula I, R is;

COR₁ wherein R₁ is selected from aminomethyl,N-(N-benzyloxycarbonylaminoacetyl)aminomethyl,N-(aminoacetyl)aminomethyl,N-(L-2-N-benzyloxycarbonylaminopropanoyl)aminomethyl,N-(L-2-aminopropanoyl)aminomethyl,N-(L-2-N-benzyloxycarbonylamino-3-methylbutyryl)aminomethyl,N-(L-2-N-benzyloxycarbonylamino-3-methylbutyryl)aminomethyl,N-(L-2-amino-3-methylbutyryl)aminomethyl,L-1-N-(benzyloxycarbonyl)aminoethyl, L-1-aminoethyl,L-1-N-(L-2-N-benzyloxycarbonylamino-3-methylbutyryl)aminoethyl,L-1-N-(L-2-N-amino-3-methylbutyryl)aminoethyl,D-1-N-(benzyloxycarbonyl)aminoethyl, D-1-aminoethyl,D-1-N-[D-2-N-(thiophen-2-yl)acetamidopropanoyl]aminoethyl,L-1-N-(benzyloxycarbonylamino-2-methyl)propyl, L-1-amino-2-methylpropyl,L-1-N-(2-N-benzyloxycarbonylaminoacetyl)amino-2-methylpropyl,L-1-N-(2-aminoacetyl)amino-2-methylpropyl,L-1-N-(L-2-N-benzyloxycarbonylamino-3-methylbutyryl)amino-2-methylpropyl,L-1-N-(L-2-amino-3-methylbutyryl)amino-2-methylpropyl,L-1-N-(L-2-amino-3-carboxypropanoyl)amino-2-methylpropyl,L-1-N-(L-2-N-benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)amino-2-methylpropyl,D-1-N-benzyloxycarbonylamino-2-methylpropyl, D-1-amino-2-methylpropyl,D-1-acetamido-2-methylpropyl,D-1-N-(D-2-N-benzyloxycarbonylamino-3-methylbutyryl)amino-2-methylpropyl,D-1-N-(D-2-amino-3-methylbutyryl)amino-2-methylpropyl,L-1-N-(benzyloxycarbonyl)amino-2-phenylethyl, L-1-amino-2-phenylethyl,L-2-N-benzyloxycarbonylamino-2-benzyloxycarbonylethyl,L-2-amino-2-carboxyethyl,L-1-benzyloxycarbonylamino-2-benzyloxycarbonylethyl,L-1-amino-2-carboxyethyl,D-1-benzyloxycarbonylamino-3-benzyloxycarbonylpropyl,D-1-amino-3-carboxypropyl, L-1-benzyloxycarbonylamino-2-benzyloxyethyl,L-1-N-(D-2-N-benzyloxycarbonylaminopropanoyl)amino-2-hydroxyethyl,L-1-N-benzyloxycarbonylamino-2-hydroxyethyl,L-1-N-(D-2-N-benzyloxycarbonylaminopropanoyl)amino-2-benzyloxyethyl,L-1-N-(L-2-N-benzyloxycarbonylamino-3-methylbutyryl)amino-2-benzyloxyethyl,L-1-N-(L-2-amino-3-methylbutyroyl)amino-2-benzyloxyethyl,L-1-acetamido-2-acetyloxyethyl, L-1-acetamido-2-hydroxyethyl,L-[1,5-di-(benzyloxy-carbonylamino)pentyl], L-[1,5-di-(acetamido)pentyl]or L-5-acetamido-1-N-benzyloxycarbonylaminopentyl.

Examples of pharmaceutically acceptable salts are sodium, potassium,calcium, magnesium or hydrogen chloride, tartaric acid, succinic acid,fumaric acid or p-toluenesulfonic acid.

Compounds of formula I may be utilized as antitumor active compounds inmedicaments, being formulated with a pharmaceutically acceptablecarrier.

The bicyclic nucleus carries two asymmetric carbon atoms at position 3and 5 and can exist as 4-diastereoisomers. In general, the preferredisomer is that in which the hydrogen atoms at C₃ and C₅ are trans toeach other for superior toxicity against different malignant cells suchas P388, KB, NUGC4, WI38, L-1210, sarcoma 180 and colon 26. Suchdiasterioisomers and their racemic mixtures are also included within theuse of the oxapenam derivatives as antitumor agents.

Antitumor activity of compounds described above is expected against somesolid cancers such as stomach, lung, breast, liver, uterus and leukemiaand so on.

DESCRIPTION OF PREFERRED EMBODIMENT

The present invention relates to the certain 3-(substitutedmethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one derivatives havingexcellent antitumor activity. The compounds of this invention arecharacterized by having ester (--OCR₁), amide (NHCOR₁) and sulfonamide(NHSO₂ R₄) linkage with alkyl, aryl, heteroaryl, amino acids ordipeptide groups which were prepared by the common starting compound 2.The preparation of compound 2 was carried out by the synthetic route asdescribed in J. Chem. Soc. Perkin Trans. I 2222, 1980, starting from4-acetoxyazetidinone. ##STR4## Wherein L and Y are suitably selectedfrom leaving groups such as chlorine, bromine, iodine,methanesulfonyloxy group, trifluoromethanesulfonyloxy group,p-toluenesulfonyloxy group and p-chlorobenzenesulfonyloxy group.

The preparation of substitutedaminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one of general formula Iwas done by synthetic route as shown below. ##STR5##

Wherein M is sodium, potassium or trimethylsilyl and R₁ is a C₁ -C₆alkyl group which may be substituted by 1-3 substituents selected fromhalogen, hydroxy, formyloxy, azido, carboxyl, heteroaryl or acetamide; aC₂ -C₄ alkenyl group; a C₂ -C₄ alkynyl group; a C₃ -C₆ cycloalkyl group;a phenyl group which may be substituted by 1-3 substituents selectedfrom hydroxy, halogen, C₁ -C₆ alkoxy group or cyano; a C₅ -C₆ heteroarylgroup; a NR₂ R₃ wherein R₂ and R₃ are the same or different and each isa hydrogen, C₁ -C₆ alkyl group or(7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl)methyl group or bezyloxygroup.

Certain 3-substituted amidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onegeneral formula I when substituent of R₁ in --COR₁ is acetamide, azide,formyloxy, hydroxy and heteroaryl, were prepared by the scheme as shownbelow. ##STR6##

Wherein n is 1 to 5; M is defined as above.

Besides the procedure described above the stereoisomer of3-acetyaminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(8,R═CH₃) wereprepared by the scheme as described below starting from3-hydroxymethyl-4-oxa-1-azabicyclo [3.2.0]heptan-7-one(1). ##STR7##

Certain derivatives of formula I wherein X is NH and R is SO₂ R₄, wereprepared by following the scheme as shown below starting from3-azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(6). ##STR8##

Wherein R₄ is the same as defined above.

The amide derivative of amino acids and dipeptides of general formula Iwere alternatively prepared by the synthetic scheme as shown below intwo steps. In the first step,3-aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(7) was coupled witheither N-protected acid in the presence of dicyclohexylcarbodiimide(DCC) or acid chloride in the presence of a base or activated esterfollowed by coupling with another N-protected amino acid which may ormay not be the same. The resulting compounds were deprotected in thepresence of H₂ and Palladium catalyst under pressure or atmosphericpressure. ##STR9##

Wherein R₅ and R₆ are selected from hydrogen, methyl, 1-methylethyl,phenylmethyl, 2-carboxyethyl, carboxymethyl, hydroxymethyl,benzyloxymethyl, acetyloxymethyl, aminobutyl and Z is benzyloxycarbonyl,acetyl, 2-thienylacetyl or tert-butoxycarbonyl.

The ester derivative of amino acids and dipeptides were prepared by thecoupling of 3-bromomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(2) withN-protected aminoacids in the presence of a base. The amine group wasdeprotected and couples with another molecule of amino acid as shown inthe scheme below. ##STR10##

Wherein R₅, R₆ and Z are defined as above.

In the above descriptions, the reactants are reacted together withsolvent at elevated or low temperatures for sufficient time to allow thereaction to proceed to completion. The reaction conditions will dependupon the nature and reactivity of the reactants. Wherever a base is usedin a reaction, they are selected from triethylamine, pyridine,4-dimethylamino-pyridine, diisopropylethylamine,1,5,-Dizabicyclo[4.3.0]non-5-ene, 1,8-Dizabicyclo[5.4.0]undec-7-ene,sodium carbonate, potassium carbonate or cesium carbonate.

The solvents of choice for the reaction are non reactive solvents suchas acetonitrile, tetrahydrofuran, ethanol, methanol, chloroform,ethylacetate, methylene chloride, dimethylformamide, dimethylsulfoxide,hexamethylphosphoric triamide or the like. Solvent mixtures may also beutilized.

Reaction temperatures would generally range from between -70° C. to 140°C. The preferred molar ratio of reactants are 1:1 to 5.0. The reactiontime range from 0.5 to 72 hours, depending on the reactants.

The deprotection of N-protective group is carried out either byhydrogenation in the presence of acids, such as hydrochloric acid oracetic acid, or by hydrolysis with appropriate acids, such ashydrochloric acid, trifluoriacetic acid or acetic acid in solvents suchas methanol, ethanol, propanol or ethylacetate. The hydrogenationreaction is usually carried out in the presence of a metal catalyst,such as Pd, Pt or Rh, under normal pressure to high pressure.

The compound of the invention, when used as an agent for treatingmalignant tumors of mammals including humans, may take pharmaceuticaldosage forms including parenteral preparations such as injections,suppositories, aerosols and the like, and oral preparations such astablets, coated tablets, powders, granules, capsules, liquids and thelike. Injections are generally preferred. The above preparations areformulated in a manner known in the art.

For the formulation of solid preparations for oral administration, anexcipient, and if desired, a binder, disintegrator, lubricant, coloringagent, corrigent, flavor, etc. are added to the compound of theinvention, and then tablets, coated tablets, granules, powders, capsulesor the like are prepared in a conventional manner.

For the formulation of injections, a pH adjusting agent, buffer,stabilizer, isotonic agents, local anesthetic or the like is added tothe active ingredient of the invention, and injections for subcutaneous,intramuscular or intravenous administration can be prepared in aconventional manner.

For the formulation of suppositories, a base, and if desired, asurfactant are added to the active ingredient of the invention, and thesuppositories are prepared in a conventional manner.

The excipients useful for the solid preparations for oral administrationare those generally used in the art, and useful examples are excipientssuch as lactose, sucrose, sodium chloride, starches, calcium carbonate,kaolin, crystalline cellulose, methyl cellulose, glycerin, sodiumalginate, gum arabic and the like, binders such as polyvinyl alcohol,polyvinyl ether, polyvinyl pyrrolidone, ethyl cellulose, gum arabic,schellac, sucrose, water, ethanol, propanol, carboxymethylcellulose,potassium phosphate and the like, lubricants such as magnesium stearate,talc and the like, and further include additives such as usual knowncoloring agents, disintegrators and the like. Examples of bases usefulfor the formulation of suppositories are, for example, oleaginous basessuch as cacao butter, polyethylene glycol, lanolin, fatty acidtriglycerides, Witepsol (trademark, Dynamite Nobel Co., Ltd.) and thelike. Liquid preparations may be in the form of aqueous or oleaginoussuspension, solution, syrup, elixir and the like, which can be preparedby a conventional way using additives.

The amount of the compound (I) of the invention to be incorporated intothe pharmaceutical composition of the invention varies with the dosageform, solubility and chemical properties of the compound, administrationroute, administration scheme and the like. Preferably the amount isabout 1 to 25 w/w % in the case of oral preparations, and about 0.1 toabout 5 w/w % in the case of injections which are parenteralpreparations.

The dosage of the compound (I) of the invention is suitably determineddepending on the individual cases taking symptoms, age and sex of thesubject and the like into consideration. Usually, the dosage in the caseof oral administration is about 50 to 1000 mg per day for an adult in 2to 4 divided doses, and the dosage in the case of injection, forexample, by intravenous administration is 2 ml (about 1 to 50 mg) whichis administered once a day for adults wherein the injection may bediluted with physiological saline or glucose injection liquid if sodesired, and slowly administered over at least 5 minutes. The dosage inthe case of suppositories is about 1 to 500 mg which is administeredonce or twice a day at an interval of 6 to 12 hours wherein thesuppositories are administered by insertion into the rectum.

REFERENCE EXAMPLE 1(3R,5S)-3-[(4-Chlorobenzenesulfonyl)oxymethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one

A mixture of(3R,5S)-3-Hydroxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one (790 mg),Triethylamne (726 mg), 4-Chlorobenzenesufonyl chloride (1.51 g) inDichloromethane was stirred for 16 hrs. The reaction mixture waspurified by silicagel column chromatography, using Chloroform-Ethylacetate (5:1) as eluent and desired sulfonate was obtained as solid.

Yield:84%.

m.p.:153.6-155.1° C., [α]_(D) ²⁵ =-90.0° (c=0.67, CDCl₃).

¹ H NMR(CDCl₃,δ):2.82(1H,d,J=16.1),2.84(1H,dd,J=5.6,5.9),3.28(1H,ddd,J=1.0,2.9,16.1),3.98(1H,dd, J=7.1,11.7),4.09(1H,dd,J=4.4, 10.8),4.21(1H,dd,J=3.6,10.8),4.47-4.58(1H,m),5.27(1H,d,J=2.6),7.56(2H,d,J=8.7),7.86(2H,d,J=8.7).

IR(Nujol,cm⁻¹):1776,1450.

REFERENCE EXAMPLE 2(3S,5S)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one

The sulfonate of reference example 1 (1.45 g) was treated with Sodiumazide (767 mg) in Dimethylformamide (10 ml) at 70° C. for 2.5 hrs. Thereaction mixture was diluted with Ethyl acetate, washed with water,brine and dried over Magnesium sulfate. The solvent was removed in vacuoand the residue was purified by silicagel column chromatography usingHexane-Ethyl acetate (2:1) as eluent.

Yield:94% (oil).

[α]_(D) ²³ =-159.0° (c=0.67,CDCl₃).

¹ H NMR(CDCl₃,δ):2.84(1H,dd,J=11.7,6.9),2.87(1H,d,J=16.2),3.26-3.38(2H,m),3.54(1H,dd,J=3.7,13.2),3.98(1H,dd,J=6.7,11.7),4.43-4.54(1H,m),5.40(1H,d,J=2.6).

IR(Neat,cm⁻¹):2960,2100,1778.

REFERENCE EXAMPLE 3Allyl[(3RS,5RS)-7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl]methylaminosuccinate

300 mg of (3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onewas hydrogenated with 200 mg of 5% Palladium on activated carbon in 30ml of Ethyl acetate at 50 psi for 1 hr. After removal of catalyst byfiltration, 20 mg(0.21 mmol) of Triethylamine, 360 mg (2.30 mmol) ofAllyl hydrogen succinate and 480 mg(2.30 mmol) of 1,3-Dicyclohexylcarbodiimide were added under ice cooling. The reaction mixture wasstirred at room temperature for 4 hrs. The resulted solid was filteredoff and the filtrate was concentrated. The residue was purified bysilica gel column using Hexane-Ethylacetate (1:1) as eluent. 150 mg oftitle compound was obtained.

Yield:30%.

¹ H NMR(CDCl₃,δ):2.47-2.96(6H,m),3.25-3.59(3H,m),3.94(1H,dd;J=6.4,11.8),4.30-4.42(1H,m),4.57-4.61(2H,m),5.21-5.37(3H,m),5.81-6.04 (2H,m).

IR(Neat,cm⁻¹):3330,2955,1783,1736.

EXAMPLE 1(3RS,5RS)-3-(N-Acetylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(1)

2.75 g of (3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one,prepared by the known method, was hydrogenated over 1.0 g of 10%Palladium on activated carbon in Ethyl acetate at 50 psi for 1 hr. Afterremoval of catalyst by filteration, 2.3 ml of Triethylamine was addedand then 1.2 ml of Acetyl chloride was added dropwise at 5° C. Thereaction mixture was then stirred for 2 hrs. The resulting mixture wasloaded on flash silicagel column and eluted with Ethyl acetate. Thetitle compound was obtained as white solid.

Yield: 67%

m.p.:59-61° C.

¹ H NMR(CDCl₃,δ):2.02(3H,s),2.64(1H,dd,J=6.5,11.7),2.84(J=16.2),3.26-3.39(2H,m),3.56(1H,ddd,J=3.6,6.5,14.3),3.96(1H,dd,J=6.5, 11.9),4.37(1H,m),5.32(1H,d,J=2,7),5.80(1H,br.s).

IR(Nujol,cm⁻¹):3565,1768,1646,1540.

EXAMPLE 2(3S,5S)-3-(N-Acetylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(2)

(3S,5S)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one of referenceexample 2 (710 mg) was hydrogenated in presence of Acetic anhydride (431mg) in Ethyl acetate (20 ml) at 50 psi for 1 hr. The reaction mixturewas purified by silicagel column chromatography using Ethylacetate-Acetone (5:1) as eluent and the title compound was obtained assolid.

Yield:89%.

m.p.:82.5-84.5° C., [α]_(D) ²⁵ =-174.0° (c=1.0, CHCl₃).

¹ H NMR(CDCl₃,δ):2.02(3H,s),2.68(1H,dd,J=7.0,11.8),2.84(1H, d,J=16.2),3.26-3.40(2H,m),3.56(1H,ddd,J=3.6,6.3,14.2),3.96(1H,dd, J=6.4,11.8),4.31-4.43 (1H,m),5.33(1H,d,J=2.5),5.86(1H,br.s).

IR(Nujol,cm⁻¹):3340,1764,1646,1540.

EXAMPLE 3(3R,5R)-3-(N-Acetylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(3)

According to the similar method as described in reference example 1,2and example 2, the title compound was obtained from(3S,5R)-3-Hydroxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one.

Yield: 87%.

m.p.:86.0-87.6° C., [α]_(D) ²⁵ =+192.0° (c=1.0, CHCl₃).

¹ H NMR(CDCl₃,δ):2.02(3H,s),2.68(1H,dd,J=7.0,11.8),2.84(1H,d,J=16.5),3.26-3.40(2H,m),3.56(1H,ddd,J=3.6,6.3,14.2),3.96(1H,dd,J=6.4,11.8),4.31-4.43 (1H,m),5.33(1H,d,J=2.6),5.87(1H,br.s).

IR(Nujol,cm⁻¹):3345,1764,1646,1542.

EXAMPLE 4(3RS,5RS)-3-(N-Hexanoylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(4)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:41%.

m.p.:56-57° C.

¹ H NMR(CDCl₃,δ):0.90(3H,t,J=6.6),1.27-1.40(4H,m),1.56-1.71(2H,m),2.20(2H,t,J=7.9),2.68 (1H,dd,J=7.0,11.8),2.84(1H,d,J=16.1),3.26-3.42(2H,m),3.55(1H,ddd,J=3.8,6.3,14.3),3.95(1H,dd,J=6.5,11.8),4.31-4.43(1H,m),5.32(1H,d,J=2.6),5.87(1H,br.s).

IR(Nujol,cm⁻¹):3320,1762,1659,1631.

EXAMPLE 5(3RS,5RS)-3-[N-(2-Methylpropanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(5)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:53%.

m.p.:76-77° C.

¹ HNMR(CDCl₃,δ):1.17(6H,d,J=6.9),2.35-2.42(1H,m),2.67(1H,dd,J=7.0,11.7),2.85(1H,d,J=16.3),3.27-3.42(2H,m),3.51-3.65(1H,m),3.96(1H,dd,J=6.4,11.8),4.30-4.45(1H,m),5.32(1H,s),5.75(1H,br.s).

IR(Nujol,cm⁻¹):3325,2960,1766.

Anal.:

calcd: C, 56.59; H, 7.60; N, 13.20

Found: C, 56.36; H, 7.79; N, 12.98

EXAMPLE 6(3RS,5RS)-3-(N-Cyclohexylcarbonylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(6)

According to the same method as described in example 1, the titlecompound was obtained as solid.

m.p.:83-85° C.

Yield:5%.

¹ H NMR(CDCl₃,δ):1.14-1.95(10H,m),2.02-2.20(1H,m),2.60-2.72(1H,dd,J=6.8,11.7),2.84(1H,d,J=16.2),3.22-3.42(2H,m),3.46-3.64(1H,m),3.95(1H,dd,J=6.5,11.8),4.31-4.43(1H,m),5.33(1H,d,J=2.7)5.68-5.82 (1H,m).

IR(Nujol,cm⁻¹):3305,2930,1781.

EXAMPLE 7(3RS,5RS)-3-[N-(Trifluoroacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(7)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:74%.

m.p.:54-57° C.

¹ H NMR(CDCl₃,δ):2.78(1H,dd,J=6.7,11.5),2.89(1H,d,J=16.8),3.30-3.492H,m),3.68(1H,ddd,J=3.4,6.5,14.3),4.03(1H,dd,J=6.5,11.9),4.37-4.49(1H,m),5.36(1H,d,J=2.7),6.62(1H,br.s).

IR(Nujol,cm⁻¹):3300,1773,1710,1550.

EXAMPLE 8(3RS,5RS)-3-(N-Chloroacetylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(8)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:51%.

m.p.:65-66.4° C.

¹ H NMR(CDCl₃,δ):2.68(1H,dd,J=6.8,11.7),2.87(1H,d,J=16.0),3.32(1H,dd,J=2.2,16.7),3.43-3.50(1H,m),3.60(1H,ddd,J=3.6,6.2,14.2),3.99(1H,dd,J=6.5,11.9),4.09(2H,s),4.36-4.46(1H,m),5.36(1H,d,J=2.6),6.88(1H,br.s).

IR(Nujol,cm⁻¹):3315,1764.

EXAMPLE 9(3RS,5RS)-3-[N-(Azidoacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(9)

(1)(3RS,5RS)-3-(N-Chloroacetylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(500mg), of example 8, and Sodium azide(297 mg) were stirred in Dimethylsulfoxide(10 ml) at room temperature for 14 hrs. The reaction mixturewas diluted with Ethyl acetate, washed with water, brine and dried overMagnesium sulfate. The residue, which obtained after removal of solventin vacuo, was purified by silicagel column chromatography (Hexane+Ethylacetate 1:2). The title compound was obtained as oil.

Yield:89%.

(2) (3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one (1.0g) was hydrogenated with 5% Palladium on activated carbon (250 mg) inEthyl acetate(20 ml)at 50 psi for 2 hrs. To the reaction mixture,Triethylamine(121 mg), Azidoacetic acid(1.21 g), 1,3-Dicyclohexylcarbodiimide(2.46 g) and Ethyl acetate(10 ml) was added and stirred for1 hr at room temperature. After removal of solid by filtration, thesolvent was removed in vacuo and the residue was purified by silicagelcolumn chromatography (Hexane-Ethyl acetate 1:3). Desired azidoacetamidewas obtained as oil.

Yield:52%.

(3) A mixture of(3RS,5SR)-3-Bromomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one (1.0 g),Azidoacetic acid (735 mg), Triethylamine (737 mg) andHexamethylphosphoric triamide(5 ml) was heated with stirring at 60-70°C. for 24 hrs. The reaction mixture was then diluted with Ethyl acetate,washed with water, brine and dried over Magnesium sulfate. The residualoil after removal of solvent in vacuo, was purified by silicagel columnchromatography using Hexane-Ethyl acetate (2:3) as eluent. The desiredazidoacetate was obtained as oil.

Yield:36%.

¹ H NMR(CDCl₃,δ):2.81(1H,dd,J=6.3,11.7),2.87(1H,d,J=16.2),3.28(1H,ddd,J=0.7,2.8,16.2),3.95(2H,s),4.02(1H,dd,J=6.9,11,7),4.29(2H,d,J=7.8),4.53-4.65 (1H,m),5.35(1H,d,J=2.7).

IR(Neat,cm⁻¹):2115,1784,1751,1193.

EXAMPLE 10(3RS,5RS)-3-[N-(1,2,3-Triazole-1-yl)acetylaminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(10)

150 mg of(3RS,5RS)-3-[N-(Azidoacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-onewas dissolved in 10 ml of Acetone and Acetylene was bubbled at -78° C.for 5 minutes. The reaction mixture was heated at 60-70° C. in seal tubefor 17 hrs. After reaction completed, solvent was removed in vacuo andthe residue was purified by silicagel column chromatography (Ethylacetate+Acetone 3:1). The title compound was obtained as oil.

Yield:69%.

¹ H NMR(CDCl₃,δ):2.57(1H,dd,J=6.9,11.7),2.82(1H,d,J=16.0),3.28(1H,dd,J=2.9,16.8),3.40-3.51(2H,m),3.94(1H,dd,J=6.5,11.9),4.29-4.41(1H,m),5.12(2H,s),5.24(1H,d,J=2.6),7.73(1H,d,J=0.8),7.80(1H,d,J=0.7)

IR(Neat,cm⁻¹):3310,1779,1689,1555.

EXAMPLE 11(3RS,5RS)-3-[N-(Formyloxyacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(11)

A mixture of(3RS,5RS)-3-(N-Chloroacetylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(260mg), Sodium formate(97 mg) in Dimethyl sulfoxide(5 ml) was stirred atroom temperature for 15 hrs, then 70° C. for 3days. The reaction mixturewas poured into water, extracted with Chloroform and dried overMagnesium sulfate. The residue which obtained after removal of solventin vacuo, was purified by flash chromatography (Ethyl acetate). Thetitle compound was obtained as oil.

Yield:33%.

¹ H NMR(CDCl₃,δ):2.68(1H,dd,J=6.7,11.6),2.86(1H,d,J=15.9),3.27-3.47(2H,m),3.64 (1H,ddd,J=3.5,6.4,14.2),4.34-4.46(1H,m),4.69(2H,s),5.34(1H,d,J=2.6),6.48(1H,br.s),8.16(1H,s).

IR(Neat,cm⁻¹):3315,1770,1719,1667,1537.

EXAMPLE 12(3RS,5RS)-3-[N-(Hydroxyacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(12)

To a solution of(3RS,5RS)-3-[N-(Formyloxyacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(55mg) in a mixture of Methanol(1 ml) and water (0.1 ml), Sodiumhydrogenecatbonate(20 mg) was added and stirred at room temperature for10 minutes. Reaction mixture was loaded directly on flash column andeluted with Ethyl acetate+Acetone (1:2). The title compound was obtainedas solid.

Yield: 69%.

m.p.:103-105° C.

¹ H NMR(CDCl₃,δ):2.54(1H,t,J=5.1),2.70(1H,dd,J=7.4,12.2),3.31(1H,dd,J=2.2,15.9),3.44(1H,dd,J=7.8,14.2),3.60(1H,ddd,J=3.8,6.3,14.2),3.98(1H,dd,J=6.5,11.8),4.16(2H,d,J=5.1),4.35-4.47(1H,m),5.35(1H,d,J=2.6),6.80 (1H,br.s).

IR(Nujol,cm⁻¹):3330,1769,1650,1531.

EXAMPLE 13(3RS,5RS)-3-[N-(6-Bromohexanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(13)

According to the same method as described in example 1, the titlecompound was obtained as oil.

Yield:50%.

¹ H NMR(CDCl₃,δ):1.50-2.40(8H,m),2.67(1H,dd,J=6.9,11.7),2.85(1H,d,J=16.1),3.38-3.76(5H,m),3.96(1H,dd,J=6.4,11.8),4.43-4.56(1H,m),5.33(1H,d,J=2.6),5.80-5.93 (1H,m).

IR(Neat,cm⁻¹):3310,1772,1639.

EXAMPLE 14(3RS,5RS)-3-[N-(6-Formyloxyhexanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(14)

According to the same method as described in example 11, the titlecompound was obtained as solid.

Yield:25%.

m.p.:61.5-63° C.

¹ H NMR(CDCl₃,δ):1.37-1.81(6H,m),2.22(2H,t,J=7.5),2.67(1H,dd,J=7.0,11.7),2.85(1H,d,J=16.2),3.28-3.65(3H,m),3.96(1H,dd,J=6.4,11.8),4.17(2H,t,J=6.6),4.32-4.42(1H,m),5.32 (1H,d,J=2.6), 5.74(1Hbr.s),8.06(1H,s).

IR(Nujol,cm⁻¹):3315,1783,1715.

EXAMPLE 15(3RS,5RS)-3-[N-(6-Azidohexanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(15)

According to the same method as described in example 9, the titlecompound was obtained as oil.

Yield:70%.

¹ H NMR(CDCl₃,δ):1.33-2.30(7H,m),2.62-2.72(1H,dd,J=6.7,11.7),2.84(1H,d,J=16.0),3.22-3.65(5H,m),5.92(1H,dd,J=6.5.11.8),4.30-4.45(1H,m),5.32(1H,d,J=2.6),5.73-5.85(1H,m).

IR(Neat,cm⁻¹):3310,2935,1772,1639.

EXAMPLE 16(3RS,5RS)-3-[N-[(1,2,3-Triazol-1-yl)hexanoyl]aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(16)

According to the same method as described in example 10, the titlecompound was obtained as solid.

Yield:37%.

m.p.:108-109° C.

¹ H NMR(CDCl₃,δ):1.24-2.04(6H,m),2.21(2H,t,J=7.3),2.65(1H,dd,J=7.2,11.9),2.83(1H,d,J=16.3),3.24-3.61(3H,m),3.94(1H,dd,J=6.4,11.8),4.30-4.46(3H,m),5.31(1H,d,J=2.6),5.74-5.87(1H,m),7.55(1H,s),7.71 (1H,s).

IR(Nujol,cm⁻¹):3315,2945,1783,1715.

EXAMPLE 17(3RS,5RS)-3-[N-(6-Acetylaminohexanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(17)

According to the same method as described in example 10, the titlecompound was obtained as solid.

Yield:10%.

m.p.:117-118° C.

¹ H NMR(CDCl₃,δ):1.33-1.76(6H,m),1.97(3H,s),2.21(2H,t,J=7.2),2.68 (1H,ddJ=7.0,11.9),2.86(1H,d,J=16.3),3.21-3.66(5H,m),3.98(1H,dd,J=6.4,11.8),4.30-4.43(1H,m),5.32(1H,d,J=2.7),5.52-5.65(1H,m),5.78-5.92(1H,m).

IR(Nujol,cm⁻¹):3275,1776,1634.

EXAMPLE 18Sodium{N-[(3RS,5RS)-7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl]methylamino}succinate(18)

The protected compound obtained in reference example 3 was dissolved ina mixture of Ethyl acetate and Dichloromethane (1:1, 4 ml) and Sodium2-ethylhexanoate(0.30 ml), Triphenylphosphine (13 mg), and Tetrakis(triphenylphosphine)palladium(0) (22 mg) were added. The reactionmixture was stirred at room temperature for 2 hrs and solid wascollected by suction. Solid was washed with Acetonitrile and dried. 65mg of the title compound was obtained as white solid.

Yield:46%.

m.p.:100° C.(dec.).

1H NMR(DMSO-d₆,δ):2.08-2.25(4H,m),2.61-2.81(2H,m),3.11-3.36(3H, m),3.76(1H,dd,J=6.6,11.5),4.27-4.33 (1H,m),5.33 (1H,d,J=2.5),8.86-8.98(1H,m).

IR(Nujol,cm⁻¹):3330,1781,1651

EXAMPLE 19(3RS,5RS)-3-[N-(4-Pentenoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(19)

600 mg of (3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onewas hydrogenated with 1.0 g of 10% Palladium on activated carbon inEthyl acetate at 50 psi for 1 hr. After removal of catalyst byfiltration, 360 mg (3.6 mmol) of 4-Pentenoic acid and 300 mg (1.8 mmol)of 1,3-Dicyclohexyl carbodiimide were added under ice-cooling. Thereaction mixture was then stirred at room temperature for 2 hrs.Resulted solid was filtered off and the filtrate was concentrated invacuo. The residue was purified by flash silicagel column usingHexane-Ethyl acetate (1:1) as eluent and the title compound was obtainedas oil.

Yield:15%.

¹ H NMR(CDCl₃,δ):2.25-2.48(4H,m),2.66(1H,dd,J=7.5,11.7),2.84(1H,d,J=16.0),3.25-3.43(2H,m),3.48-3.64(1H,m),3.97(1H,dd,J=6.5,11.8),4.31-4.44(1H,m),4.98-5.14(2H,m),5.33(1H,d,J=2.6),5.75-5.92(2H,m).

IR(Neat,cm⁻¹):3275,1776,1634.

EXAMPLE 20(3RS,5RS)-3-[N-Propynoylaminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(20)

According to the same method as described in example 19, the titlecompound was obtained as solid.

Yield:29%.

m.p.:76.5-78° C.

¹ H NMR(CDCl₃,δ):2.68(1H,dd,J=5.3,10.0),2.87(1H,s),2.88(1H,d,J=10.5),3.33(1H,d,J=11.1),3.63(1H,ddd,J=2.6,4.7,10.0),3.99(1H,dd,J=4.7,7.9),4.36-4.44 (1H,m),5.35(1H,d,J=2.1),6.20(1H,br.s).

IR(Nujol,cm⁻¹):3270,2115,1782,1657.

EXAMPLE 21(3RS,5RS)-3-[N-(Benzyloxycarbonyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(21)

According to the same method as described in example 1, the titlecompound was obtained as oil.

Yield:54%.

¹ HNMR(CDCl₃,δ):2.70(1H,dd,J=6.8,12.3),2.86(1H,d,J=16.6),3.22-3.55(1H,m),3.96(1H,dd,J=5.1,11.5),4.31-4.47(1H,m),5.06(1H,br.s),5.10(2H,s),5.31(1H,d,J=2.6).

EXAMPLE 22 (3RS,5RS)-3-aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride (22)

890 mg of (3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onewas hydrogenated as described in example 1. After removal of catalyst byfiltration, 5 ml of 1N-HCl was added at -78° C. Water layer was thenseparated and lyophilized. The title compound was obtained as paleyellow solid.

Yield:73%.

¹ HNMR(CDCl₃,δ):2.78-2.86(1H,m),2.82(1H,d,J=15.6),2.98(1H,d,J=6.12),3.99(1H,d,J=15.6),3.87(1H,dd,J=6.7,11.7),4.54-4.57(1H,m),5.38(1H,dd,J=2.6),8.38(2H,br.s).

IR(Nujol,cm-1):3325,1806,1775.

EXAMPLE 23(3RS,5RS)-3-(N-Benzoylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(23)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield: 53%.

m.p.:115-116° C.

¹ H NMR(CDCl₃,δ):2.76(1H,dd,J=7.3,11.6),2.86(1H,d,J=16.7),3.31(1H,dd,J=2.9,16.8),3.49-3.62(1H,m),3.78(1H,ddd,J=3.5,6.4,14.2),4.02(1H,dd,J=6.4,11.8),4.42-4.55(1H,m),5.36(1H,d,J=2.7),6.46(1H,br.s),7.40-7.57(3H,m),7.76-7.81(2H,m).

IR(Nujol,cm⁻¹):3335,1779,1639,1534.

Anal.:

calcd: C, 63.40; H, 5.73; N, 11.38

Found: C, 63.39; H, 5.69; N, 11.25

EXAMPLE 24(3RS,5RS)-3-[N-(4-Hydroxybenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(24)

According to the same method as described in example 19, the titlecompound was obtained as oil.

Yield:25%.

¹ HNMR(CDCl₃,δ):2.76(1H,dd,J=6.2,11.5),2.79(1H,d,J=16.3),3.29-3.55(3H,m),3.80(1H,dd,J=6.6,11.5),4.41-4.47(1H,m),5.33(1H,d,J=2.5),6.79(2H,d,J=8.7),7.72(2H,d,J=8.7),8.37(1H,br.s),9.97(1H,s).

IR(Nujol,cm⁻¹):3315,1765,1600.

EXAMPLE 25(3RS,5RS)-3-[N-(4-Methoxybenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(25)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:23%.

m.p.:142.6° C.

¹ H NMR(CDCl₃,δ):2.75(1H,dd,J=7.4,12.2),2.86(1H,d,J=16.7),3.31(1H,dd,J=2.9,15.9),3.47-3.61(1H,m),3.76(1H,ddd,J=3.6,6.4,14.3),3.86(3H,s),4.01(1,dd,J=6.5,11.9),4.42-4.54(1H,m),5.36(1H,d,J=2.7),6.35(1H,br.s),6.94(2H,d,J=8.8),7.75(2H,d,J=8.9).

IR(Nujol,cm⁻¹):3290,1774,1625.

EXAMPLE 26(3RS,5RS)-3-[N-(3,4-Dimethoxybenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(26)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:45%.

m.p.:170-190° C. (dec.).

¹ H NMR(CDCl₃,δ):2.76(1H,dd,J=7.0,11.8),2.89(1H,d,J=9.1),3.32(1H,dd,J=2.4, 16.5),3.52-3.81(2H,m),3.93(3H,s),3.94(3H,s),4.02(1H,dd,J=6.5,11.9),4.46-4.51(1H,m),5.36(1H,d,J=2.6),6.38(1H,br.s),6.87(1H,d,J=8.3),7.26-7.31(1H,m),7.43(1H,d,J=2.0).

IR(Nujol,cm⁻¹):3370,2850,1794,1774.

EXAMPLE 27(3RS,5RS)-3-[N-(4-Fluorobenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(27)

According to the same method as described in example 1, the titlecompound was obtained as oil.

Yield:16%.

¹ H NMR(CDCl₃,δ):2.67(1H,dd,J=6.9,11.7),2.78(1H,d,J=16.6),3.23(1H,dd,J=2.8,16.6),3.39-3.52(2H,m),3.67(1H,ddd,J=3.7,6.3,14.3),3.93(1H,dd,J=6.5,11.9),4.35-4.46(1H,m),5.28(1H,d,J=2.6),6.56(1H,br.s),7.00-7.08(2H,m),7.69(2H,m).

IR(Nujol,cm⁻¹):3345,2965,1783.

EXAMPLE 28(3RS,5RS)-3-[N-(2,5-Difluorobenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(28)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:43%.

m.p.:88.8-90.7° C.

¹ H NMR(CDCl₃,δ):2.76(1H,dd,J=7.1,11.8),2.87(1H,d,J=16.4),3.32(1H,dd,J=2.6,16.3),3.57-3.80(2H,m),4.02(1H,dd,J=6.5,11.8),4.44-4.56(1H,m),5.38(1H,d,J=2.6),7.06-7.20(3H,m),7.42(1H,m).

IR(Nujol,cm⁻¹):3340,2935,1776.

Anal.:

calcd: C, 55.30; H, 4.29; N, 9.93

Found: C, 55.05; H, 4.18; N, 9.74

EXAMPLE 29(3RS,5RS)-3-[N-(2,4,5-Trifluorobenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(29)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:45%.

m.p.:76.5-78.1° C.

¹ H NMR(CDCl₃,δ):2.74(1H,dd,J=7.1,11.8),2.87(1H,d,J=16.3),3.33(1H,d,J=16.4),3.57-3.72(2H,m),4.02(1H,dd,J=6.5,11.8),4.67-4.52(1H,m), 5.38(1H,s),6.96-7.09(2H,m),7.89-8.02(1H,m).

IR(Nujol,cm⁻¹):3300,2960,1786.

Anal.:

calcd: C, 52.01; H, 3.69; N, 9.33

Found: C, 51.79; H, 3.49; N, 9.15

EXAMPLE 30(3RS,5RS)-3-[N-(4-Cyanobenzoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(30)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:45%.

m.p.:130-170° C.(dec.).

¹ H NMR(CDCl₃,δ):2.74(1H,dd,J=6.9,11.8),2.86(1H,d,J=16.5),3.26(1H,dd,J=2.9,16.7),3.46-3.60(1H,m),3.80(1H,ddd,J=3.5,6.4,14.2),4.03(1H,dd,J=6.4,11.8),4.43-4.55(1H,m),5.37(1H,d,J=2.6),6.65(1H,br.s),7.75(2H,d,J=8.5),7.90(2H,d,J=8.5).

IR(Nujol,cm⁻¹):3360,2235,1795,1774.

EXAMPLE 31(3RS,5RS)-3-[N-(Thiophen-2-yl)acetylaminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(31)

500 mg (3.0 mmol) of(3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one washydrogenated as usual manner. The solution was filtered through celiteand to the filtrate 0.8 ml of Triethylamine was added. Under cooling,Thiophen-2-yl-acetyl chloride, prepared from 1.0 g ofThiophen-2-yl-acetic acid, was slowly added to it and the mixture wasstirred at room temperature for 1 hr. The solution was filtered throughsilica gel column and the title compound was obtained as oil.

Yield:18%.

¹ H NMR(CDCl₃,δ):2.63(1H,dd,J=7.26),2.80(1H,d,J=16.2),3.26(1H,dd,J=2.3,16.0),3.40-3.48(2H,m),3.81(2H,s),3.92(1H,dd,J=6.5,11.9),4.28-4.40(1H,m),5.16(1H,d,J=2.6),5.88(1H,br.s),6.93-7.04(2H,m),7.23-7.30(1H,m).

IR(Nujol,cm⁻¹):3310, 1767, 1644.

EXAMPLE 32(3RS,5RS)-3-[N-[(Pyridin-3-yl)carbonyl]aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(32)

According to the same method as described in example 19, the titlecompound was obtained as oil.

Yield:7%.

¹ H NMR(CDCl₃,δ):2.75(1H,dd,J=6.9,11.8),2.88(1H,d,J=16.2),3.34(1H,dd,J=2.2,16.0),3.46-3.63(1H,m),3.82(1H,ddd,J=3.4,6.4,14.3), 4.04(1H,dd,J=6.4,11.9),4.44-4.56(1H,m),5.38(1H,d,J=2.7),6.54 (1H,br.s),7.43(1H,dd,J=4.8,7.7),8.15(1H,dt,J=2.2,7.8),8.78(1H,dd,J=1.6,4.9),9.00(1H,d,J=1.8).

EXAMPLE 33(3RS,5RS)-3-[N-(N,N-Diethylcarbamyl)]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(33)

According to the same method as described in example 1, the titlecompound was obtained as oil.

Yield: 31%.

¹ H NMR(CDCl₃,δ):1.13(6H,t,J=7.2),2.72(1H,dd,J=7.2,12.0),2.84 (1H,dd,J=16.0),3.21-3.34(3H,m),3.54(1H,ddd,J=3.6,6.3,1.3),3.95(1H,dd,J=6.5,11.8),4.34-4.46(1H,m),4.46(1H,br.s),5.31(1H,d,J=2.7).

IR(Neat,cm⁻¹):3355,1780,1629.

EXAMPLE 34N,N'-Di-{[(3RS,5RS)-7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl]methyl}urea(34)

A solution of 340 mg(2.0 mmol) of(3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one in 30 mlof Ethyl acetate was hydrogenated under 45 psi with 150 mg of 10%Palladium on activated carbon. The reaction mixture was filtered throughcelite and concentrated to 15 ml at cool temperature. At this point,Phosgene (20% in Toluene, 260 mg, 2 mmol) was added dropwise while thepH of the mixture was kept at 7 by adding of a saturated solution of K₂CO₃. The reaction mixture was extracted with Ethyl acetate (3×20 ml) andthe combined organic layer was dried over MgSO₄ and concentrated.Crystallization of the yellow residue in Ethyl acetate gave product as awhite prisms.

Yield:42%.

m.p.: >300° C.(dec.).

¹ H NMR (DMSO-d₆,δ):2.64(2H,dd,J=6.4,11.5),2.77(2H,d,J=16.3),3.18(4H,t,J=5.4),3.33(2H,dd,J=2.7,16.2),4.22-4.34(2H, m),5.30(2H,d,J=2.6),6.15(2H,br.t,J=5.8).

IR(Nujol,cm⁻¹):3320,1770.

EXAMPLE 35(3RS,5RS)-3-(N-Methanesulfonylaminomethyl)-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(35)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:23%.

m.p.:115-190° C. (gradually dec.).

¹ H NMR(CDCl₃,δ):2.82(1H,dd,J=7.5,11.8),2.87(1H,d,J=16.8),3.01(3H,s),3.22-3.67(3H,m),4.00(1H,dd,J=6.4,11.9),4.35-4.49(1H,m),4.58(1H,br.s),5.35(1H,d,J=2.8).

IR(Nujol,cm⁻¹):3235,1783,1302.

EXAMPLE 36(3RS,5RS)-3-[N-(4-Toluenesulfonyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(36)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:74%.

m.p.:123-125° C.

¹ HNMR(CDCl₃,δ):2.44(3H,s),2.74(1H,dd,J=11.6,7.4),2.81(1H,d,J=15.8),2.97-3.21(2H,m),3.28(1H,dd,J=2.2,15.9),3.01(1H,dd,J=11.9,17.3),4.26-4.38(1H,m),4.78(1H,br.t,J=6.3),5.26(1H,d,J=2.6),7.33(2H,d,J=8.1),7.74(2H,d,J=8.3).

IR(Nujol,cm⁻¹):3275,1778,1153.

EXAMPLE 37(3RS,5RS)-3-[N-(4-Chlorobenzenesulfonyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(37)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:35%.

m.p.:101-103° C.

¹ HNMR(CDCl₃,δ):2.78(1H,dd,J=7.4,11.6),2.82(1H,d,J=15.9),2.99-3.23(2H,m),3.29(1H,dd,J=6.5,11.9),4.28-4.40(1H,m),4.89(1H,br.t,J=6.4),5.27(1H,d,J=2.7),7.51(2H,d,J=8.7),7.80(2H,d,J=8.7).

IR(Nujol,cm⁻¹):3275,1764,1320,1153.

EXAMPLE 38(3RS,5RS)-3-N-(4-Methoxybenzenesulfonyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(38)

According to the same method as described in example 1, the titlecompound was obtained as solid.

Yield:66%.

m.p.:116.5-118.5° C.

¹ H NMR(CDCl₃,δ):2.79(1H,dd,J=5.3,7.3),2.80(1H,d,J=16.0),2.96-3.21(3H,m),3.27(1H,dd,J=2.5,16.7),3.88(3H,s),3.92(1H,dd,J=5.4,6.5),4.24-4.38(1H,m),4.89(1H,br.t,J=6.4),5.26(1H,d,J=2.6),6.99(2H,d,J=8.9),7.79(2H,d,J=8.9).

IR(Nujol,cm⁻¹):3265,1770,1578,1489.

EXAMPLE 39(3RS,5SR)-3-(Aminoacetyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride (39)

Azidoacetate(390 mg) obtained in example 9, 5% Palladium on activatedcarbon(390 mg) were shaken in Ethanol-Ethyl acetate(10 ml each) at 50psi for 1 hr. After the reaction, catalyst was removed by filtration and1.5 ml of 1N-HCl was added under cooling condition. Reaction mixture waspurified on HP-20 column by elution with water. The title compound wasobtained after lyophylization as solid.

Yield:46%.

m.p.:85-110° C.(dec.).

¹ H NMR(DMSO-d₆,δ):2.76-2.88(1H,m),2.80(1H.d,J=16.3),2.98(1H,d,J=9.4),3.83-4.28(6H,m),4.57-4.83(1H,m),5.36(1H,d,J=2.5),7.66(1H,br.s),8.43 (2H,br.s).

IR(Nujol,cm⁻¹):3205,1751,1651.

EXAMPLE 40(3RS,5SR)-3-[N-(N-Benzyloxycarbonylaminoacetyl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(40A) and(3RS,5SR)-3-[N-(Aminoacetyl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(40B)

A mixture of(3RS,5SR)-3-Bromomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one (2.0g,9.71 mmol), N-(benzyloxycarbonylaminoacetyl)aminoacetic acid (2.6g,11.6 mmol) and Cesium carbonate (3.8 g, 11.6 mmol) inHexamethylphosphoric triamide (15 ml) was stirred at 65-70° C. for 2hrs. Resulting mixture was poured onto ice-water and extracted withEthyl acetate. The extract was washed with water, brine and dried overMagnesium sulfate. Solvent was removed in vacuo and the residue waspurified on a silica gel column chromatography using ethylacetate-acetone (9:1) as the eluent gave an off-white solid (40A).

Yield:3.0 g (79%).

¹ H NMR (DMSO-d₆,δ):2.70-2.85(2H,m),3.30(1H,dd,J=16.1,2.4),3.62-4.20(7H,m),4.48-4.62(1H,m),5.11(2H,s),5.32(1H,d,J=2.5),7.35(5H,s),7.55(1H,t,J=5.7),8.35(1H,t,J=5.7).

IR(Nujol,cm⁻¹):3461,3405,1781,1750,1722,1636.

N-(benzyloxycarbonylaminoacetyl)aminoacetoxy derivative, obtained above(1.1 g,2.81 mmol) and Palladium on activated carbon (10%, 53.8% moist,0.8 g) in Methanol (140 ml) was shaken at 50 psi for 1 hr under Hydrogenatmosphere. After the reaction, catalyst was filtered off using celitepad. The filtrate was concentrated in vacuo and the residue wasre-dissolved in Ethyl acetate. Acidification (1N HCl 2.4 ml, water 26ml) and followed by freeze-drying gave a solid (40B).

Yield:660 mg(80%).

¹ H NMR(DMSO-d₆,δ):2.62-2.76(2H,m),3.10-4.14(8H,m),4.44-4.55(1H,m),5.27(1H,d,J=2.5Hz),8.23(3H.br.s),8.94(1H,t,J=5.7).

IR(Nujol,cm⁻¹):3125,1774,1748,1682,1618.

EXAMPLE 41(3RS,5SR)-3-[N-(L-2-N-Benzyloxycarbonylaminopropanoyl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(41A)and(3RS,5SR)-3-[N-(L-2-Aminopropanoyl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(41B)

A solution of(3RS,5SR)-3-[N-(Benzyloxycarbonyl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(1.0 g,2.99 mmol) in Ethyl acetate (80 ml) was hydrogenolysed at 50 psifor 15 hr using Palladium on activated carbon (10%,53.8% moist,0.75 g).The mixture was filtered through a pad of celite and cooled in anice-bath. 1,3-Dicyclohexyl carbodiimide (740 mg,3.58 mmol) was added toan ice-cold solution of N-Benzyloxycarbonyl-L-2-aminopropanoic acid(1.33 g,5.98 mmol) in Ethyl acetate (80 ml) and the mixture was stirredfor 1 hr. The N-Benzyloxycarbonyl-L-2-aminopropanoic acid-DCC complexwas added to the ice-cold Ethyl acetate solution of the amine preparedabove. The mixture was stirred at room temperature overnight. Theprecipitated urea was filtered off, the filtrate was concentrated andpassed through a silica gel column using Ethyl acetate as the eluent togive a thick oil (41A).

Yield:83%.

¹ H NMR(CDCl₃,δ):1.40(3H,d,J=7.1),2.74-2.88(2H,m),3.29(1H,dd,J=16.4,2.7),3.93-4.60(6H,m),5.11(2H,m),5.29-5.41(2H,m),5.35(1H,br.s),6.74(1H,br.s),7.34(5H,s).

(N-protected aminopropanoyl)aminoacetyl ester derivative was deprotectedas same manner described in example 40 and the title compound(41B) wasobtained as solid.

Yield:720 mg(63%).

¹ HNMR(DMSO-d₆,δ):1.41(3H,d,J=6.9),2.75-2.83(2H,m),3.31(1H),3.81-4.24(6H,m),4.55(1H,m),5.34(1H,d,J=2.4),8.39(3H,br.s),9.12(1H,br.s).

IR(Nujol,cm⁻¹):3345,3195,1770,1746,1681.

EXAMPLE 42(3RS,5SR)-3-[N-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(42A) and(3RS,5SR)-3-[N-(L-2-Amino-3-methylbutyryl)aminoacetyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(42B)

According to the same manner described as in example 40,L-(2-N-benzyloxycarbonylamino-3-methylbutyl)aminoacetic acid was coupledwith (3RS,5SR)-3-Bromomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one andN-protected title compound(42A) was obtained as off-white solid.

Yield:83%.

m.p.:143-145° C.

¹ H NMR(CDCl₃,δ):0.94(3H,d,J=6.8),0.98(3H,d,J=6.8),2.09-2.25(1H,m),2.73-2.88(2H,m),3.29(1H,dd,J=16.3,2.4),3.93-4.31(7H,m),4.48-4.59(1H,m),5.11(2H,s),5.32-5.40(2H,m),6.58(1H,br.t),7.34(5H,s).

IR(Nujol,cm⁻¹):3295,1793,1750,1687,1647,1619.

The benzyloxycarbonyl group was hydrogenolysed according to the samemanner described as in example 40, the title compound(42B) was obtainedas solid.

Yield:64%.

¹ H NMR(DMSO-d₆,δ):0.91(6H,d,J=6.8),2.02-2.12(1H,m),2.66-2.76(2H,m),3.29(1H,dd,J=16.1,2.6),3.62-4.17(6H,m),4.40-4.55(1H,m),5.26(1H,d,J=2.5),8.25(3H,br.s),9.0(1H,br.t).

IR(Nujol,cm⁻¹):3195,1776,1750,1677,1621.

EXAMPLE 43(3RS,5RS)-3-N-(Aminoacetyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(43)

Azidoacetamide compound, obtained in reference example 9 (890 mg), washydrogenated in presence of 5% Palladium on activated carbon(800 mg) inEthanol(20 ml) at 50 psi for 2 hr. After removal of catalyst byfiltration, 3.0 ml of 1N-HCl was added under cooling condition andsolvent was removed in vacuo. The residue was purified on HP-20 columnusing water as eluent and the title compound was obtained afterlyophilization as yellow solid(43).

Yield:62%.

¹ HNMR(CDCl₃,δ):2.70(1H,dd,J=6.5,11.6),2.79(1H,d,J=16.4),3.19-3.44(3H,m),3.56(2H,s),3.82(1H,dd,J=6.5,11.6),4.27-4.39(1H,m),5.34(1H,d,J=2.6),8.21(2H,br.s),8.72(1H,br.t,J=5.6).

IR(Nujol,cm⁻¹):3255,1768.

EXAMPLE 44(3RS,5RS)-3-N-(N-Acetylaminoacetyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(44)

Acetic anhydride(17 ml) was added dropwise at 5° C. to a mixture ofN-(aminoacetyl)aminomethyl amido derivative which was obtained inexample 45(20 mg) and Triethylamine(17 mg) in Dichloromethane(1 ml). Themixture was stirred under same condition for 30 minutes. The reactionmixture was purified by silicagel column chromatography using Acetone aseluent and title compound(44) was obtained as white solid.

Yield:44%.

m.p.142-144° C.

¹ HNMR(CDCl₃,δ):1.85(3H,s),2.66(1H,dd,J=6.4,11.5),2.78(1H,d,J=16.3),3.14-3.38(3H,m),3.65(2H,d,J=10.2),3.77(1H,dd,J=6.6,11.6),4.24-4.36 (1H,m),5.30(1H,d,J=2.6),7.99-8.08(2H,m).

IR(Nujol,cm⁻¹):3280,3095,1800,1636.

EXAMPLE 45(3RS,5RS)-3-[N-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)aminoacetyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(45A) and(3RS,5RS)-3-[N-(L-2-amino-3-methylbutyryl)aminoacetyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(45B)

According to the same manner as described in example 41, N-protectedtitle compound(45A) was obtained as solid.

Yield:23%.

¹ H NMR(DMSO-d₆,δ):0.79(6H,m),1.84-1.94(1H,m),2.54-2.74(2H,m),3.15-3.29(5H,m),3.62-3.80(3H,m),4.19-4.25(1H,m),4.96(2H,s),5.23(1H,d,J=2.6),7.29(5H,s),7.82(1H,br.t),8.15(1H,br.s).

N-protected amide derivative, obtained as above, was deprotected as samemanner described in example 43 and the title compound(45B) was obtainedas solid.

Yield:0.40 g(70%).

¹ HNMR(DMSO-d₆,δ):0.80(6H,m),1.94-2.10(1H,m),2.60-2.74(2H,m),3.05-3.35(5H,m),3.50-3.80(3H,m),5.25(1H,d,J=2.6),8.35(3H,br.s),8.80(1H,br.s).

IR(Nujol,cm⁻¹):3195,1782,1718,1678,1653,1603.

EXAMPLE 46(3RS,5RS)-3-N-[N-(L-2-N-Benzyloxycarbonylamino-3-carboxypropanoyl)aminoacetyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(46A) and(3RS,5RS)-3-N-[N-(L-2-Amino-3-carboxypropanoyl)aminoacetyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(46B)

Azidoacetamide derivative of clavam compound, obtained in example 43,was coupled with protected aspartic acid derivative using similar methoddescribed in example 41 and the protected title compound wasobtained(46A).

Yield:42%.

¹ H NMR(CDCl₃,δ):2.62-2.88(2H,m),2.76(1H,d,J=16.6),3.10-3.25(2H,m),3.34-3.42(2H,m),3.77-4.17(3H,m),4.30-4.40(1H,m),4.53-4.63(1H,m),5.13(4H,s),5.28(1H,t,J=3.1),5.75-5.82(1H,m),6.67-6.75(1H,m),6.94-7.03(1H,m),7.30-7.38(10H,m).

0.5 g of the protected compound and 0.5 g of 5% Palladium on activatedcarbon in 10 ml Methanol was stirred under Hydrogen atmosphere at normalpressure for 2.5 hrs. Later the catalyst was filtered through celite andfiltrate was concentrated. Acetonitrile was added to the residue andsolid was collected by filtration(46B).

Yield:34%.

m.p.:200° C.(dec.).

¹ H NMR(CDCl₃,δ):2.64-2.69(1H,m),2.77(1H,d,J=16.2),3.08-3.85(6H,m), 3.32(1H,d,J=13.4),4.25-4.38(1H,m),5.30(1H,d,J=2.4),8.25-8.56 (2H,m).

IR(Nujol,cm⁻¹):3290,1773.

EXAMPLE 47(3RS,5RS)-3-N-[N-(D-4-N-benzyloxycarbonylamino-4-benzyloxycarbonylbutyryl)aminoacetyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(47A)and(3RS,5RS)-3-N-[N-(D-4-Amino-4-carboxybutyryl)aminoacetyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(47A)

(3RS,5RS)-3-[N-(Azidoacetyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one,obtained in example 43, was coupled with[4-(Benzyloxycarbonylamino)-4-benzyloxycarbonyl]butyric acid usingsimilar method described in example 41 and the protected title compoundwas obtained(47A).

Yield:21%.

m.p.:45° C.

¹ H NMR(CDCl₃,δ):1.97-2.19(1H,m),2.17-2.30(1H,m),2.40-2.50(2H,m),2.73(1H,dd,J=6.1,11.6),3.25(1H,d,J=16.2),3.94(1H,dd,J=6.9,11.6),4.05-4.20(4H,m),4.40-4.55(2H,m),5.10(2H,m),5.17(2H,m),5.30(1H,t,J=2.8),5.39(br.s),7.35(10H,s).

IR(Neat,cm⁻¹):3355,1784,1739,1525.

This protected amide derivative obtained above was deprotected by usingsame method as described in example 46 and the title compound(47B) wasobtained as solid.

Yield:10%.

m.p.:220° C.(dec).

¹ H NMR(DMSO-d₆,δ):1.90-2.04(2H,m),2.75(1H,dd,J=5.9,16.4),2.50-2.57(4H,m),2.80(1H,d,J=16.4),3.33(1H,dd,J=2.6,16.2),3.84(1H,dd,J=7.1,11.6),4.12(2H,d,J=3.4),4.22-4.47(1H,m),5.29(1H,d,J=2.5),5.08-5.21(1H,br.d).

EXAMPLE 48(3RS,5SR)-3-(L-2-N-Benzyloxycarbonylaminopropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(48A)and(3RS,5SR)-3-(L-2-Aminopropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(48B)

According to the same method described in example 40, N-protected titlecompound(48A) was obtained as oil.

Yield:68%.

¹ HNMR(CDCl₃,δ):1.44(3H,d,J=7.2),2.70-2.87(1H,m),2.84(1H,d,J=16.2),3.27(1H,d,J=16.0),3.98(1H,dd,J=7.1,11.6),4.18-4.56(2H,m),4.30-4.65(2H,m),5.12(2H,s),5.18-5.30(1H,m),5.32(1H,s),7.35(5H,s).

IR(Neat,cm⁻¹):3550,1784,1748,1720,1525.

The N-protected ester derivative obtained above was deprotected bycatalytic hydrogenation in Methanol using 5% Palladium on activatedcarbon at room temperature (50 psi, 1 hr). After removal of catalyst,1N-HCl(1.7 ml) was added to the reaction mixture under cooling conditionand resulted solution was then purified by HP-20 column chromatographyusing water as eluent. The title compound(48B) was obtained afterlyophilization as solid.

Yield:15%.

1HNMR(DMSO-d₆,δ):1.43(3H,d,J=7.4),2.70-2.89(1H,m),2.80(1H,d,J=15.7),3.26-3.40(1H,m),3.88(1H,dd,J=6.7,11.8),4.02-4.37(4H,m),4.50-4.70 (1H,m),5.35(1H,t,J=3.4),8.57(2H,br.s).

IR(Nujol,cm⁻¹):3400,3275,1746.

EXAMPLE 49(3RS,5SR)-3-[L-2-N-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)aminopropanoyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(49A) and (3RS,5SR)-3-[L-2-N-(L-2-Amino-3-methylbutyryl)aminopropanoyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(49B)

According to the same method as described in example 41, protected titlecompound(49A) was obtained as an off-white solid.

Yield:65%.

m.p.:167-169° C.

¹ H NMR(CDCl₃,δ):0.93(3H,d,J=6.8),0.98(3H,d,J=6.8),1.35(3H,d,J=2.04-2.18(1H,m),2.73-2.89(2H,m),3.33(1H,dd,J=16.2,2.6),3.94-4.03(2H,m),4.21-4.25(2H,m),4.55-4.62(2H,m),5.11(2H,s),5.35(2H,br.s),6.30(1H,d,J=7.1),7.35(5H,s).

IR (Nujol,cm⁻¹):3315,1785,1746,1688,1648.

The N-protected ester derivative was deprotected as same mannerdescribed in example 40 and the title compound(49B) was obtained assolid.

Yield:66%.

¹ H NMR(DMSO-d₆,δ):0.98(6H,d,J=6.8),1.35(3H,d,J=7.2),2.12-2.15(1H,m),2.75-2.83(2H,m),3.31-3.38(1H,m),3.64-4.56(6H,m),5.35(1H,d,J=2.9),8.30(3H,br.s),9.06(1H,br.d,J=6.6).

IR(Nujol,cm⁻¹):3120,1792,1763,1740,1683,1650.

EXAMPLE 50(3RS,5RS)-3-N-(L-2-N-Benzyloxycarbonylaminopropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(50A)and(3RS,5RS)-3-N-(L-2-Aminopropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(50B)

According to the same procedure described in example 43, N-protectedtitle compound(50A) was obtained.

Yield:68%.

¹ HNMR(CDCl₃,δ):1.42(3H,d,J=17.3),2.72-2.57(1H,m),2.81(1H,d,J=16.6),3.48(1H,dd,J=3.4,16.6),3.33-3.57(2H,m),3.85-4.00(1H,m),4.16-5.76(2H,m),5.12(2H,s),5.26-5.31(1H,m),6.39(1H,br.s),7.33 (5H,s).

IR(Neat,cm⁻¹):3295,1782,1653,1533.

The title compound(50B) was obtained after deprotection as described inexample 43, followed by salt formation.

1HNMR(DMSO-d₆,δ):1.35(3H,d,J=6.9),2.65-2.70(1H,m),2.79(1H,dd,J=3.1,16.4),3.10-3.50(3H,m),3.77-3.90(2H,m),4.27-5.92(1H,m),5.32(1H,t,J=3.1),8.12 (2H,br.s),8.68(1H,m).

IR(Nujol,cm⁻¹):3380,3230,1774,1670,1562.

EXAMPLE 51(3RS,5SR)-3-(D-2-N-Benzyloxycarbonylaminopropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(51A)and(3RS,5SR)-3-(D-2-Aminopropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(51B)

According to the same procedure described in example 43, N-protectedtitle compound(51A) was obtained as oil.

Yield:58%.

¹ HNMR(CDCl₃,δ):1.44(3H,d,J=7.2),2.20-2.56(1H,m),5.68(1H,d,J=16.3),6.54(1H,d,J=15.9),3.97(1H,dd,J=7.0,11.6),4.17-4.25(2H,m),4.38-4.63(2H,m),5.11(2H,s),5.25(1H,br.d,J=6.4),5.32(1H,s),7.35 (5H,m).

IR(Neat,cm⁻¹):3355,1704,1748,1720,1526.

The title compound(51B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:18%.

¹ H NMR(DMSO-d₆,δ):2.87(3H,d,J=7.4),2.71-2.92(2H,m),3.30-3.94(1H,m),3.88(1H,dd,J=6.9,11.8),3.96-4.44(3H,m),4.50-4.69(1H,m),5.35(1H,t,J=3.5),8.57(1H,br.s).

IR(Nujol,cm⁻¹):3400,1746,1645.

EXAMPLE 52(3RS,5SR)-3-{D-2-N-[D-2-N-(Thiophen-2-yl)acetylaminopropanoyl]aminopropanoyl}oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(52)

According to the similar method as described in example 40, the titlecompound(52) was obtained as solid.

Yield:

m.p.:122-125° C.

¹ HNMR(CDCl₃,δ):1.34(3H,d,J=7.0),1.40(3H,d,J=7.2),2.80(1H,dd,J=6.3,17.9),2.85(1H,d,J=16.4),3.30(1H,dd,J=2.6,16.2),3.78(2H,s),3.97 (1H,dd,J=6.7,11.6),4.20-4.26(2H,m),4.47-4.55(2H,m),5.32-5.35(1H,t,J=3.3),6.23 (1H,br.d,J=7.1),6.67(1H,br.d,J=7.1),6.95-7.01(2H,m),7.24-7.26(1H,m).

IR(CHCl₃,cm⁻¹):3295,1778,1747,1646.

EXAMPLE 53(3RS,5RS)-3-N-(D-2-N-Benzyloxycarbonylaminopropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(53A)and(3RS,5RS)-3-N-(D-2-Aminopropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(53B)

According to the same method described in example 43, N-protected titlecompound(53A) was obtained as oil.

Yield:60%.

¹ HNMR(CDCl₃,δ):1.42(3H,d,J=17.3),2.72-2.57(1H,m),2.81(1H,d,J=16.6),3.48(1H,dd,J=3.3,16.6),3.33-3.57(2H,m),3.85-4.00(1H,m),4.16-5.76(2H,m),5.12(2H,s),5.26-5.31(1H,m),6.39(1H,br.s),7.33 (5H,s).

IR(Neat,cm⁻¹):3295,1782,1653,1533.

The title compound(53B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:73%.

1HNMR(DMSO-d₆,δ):1.35(3H,d,J=6.9),2.65-2.70(1H,m),2.79(1H,dd,J=3.1,16.4),3.10-3.50(3H,m),3.77-3.90(2H,m),4.27-5.92(1H,m),5.32(1H,t,J=3.1),8.12 (2H,br.s),8.68(1H,br.s).

IR(Nujol,cm⁻¹):3380,3230,1774,1670,1562.

EXAMPLE 54(3RS,5SR)-3-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(54A)and(3RS,5SR)-3-(L-2-Amino-3-methylbutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(54B)

According to the same procedure described in example 43, N-protectedtitle compound(54A) was obtained as oil.

Yield:49%.

¹ H NMR(CDCl₃,δ):0.91(3H,d,J=6.9),0.98(3H,d,J=6.8),2.13-2.22(1H,m),2.84(2H,d,J=16.3),3.23-3.33(1H,m),4.00(1H,dd,J=7.0,11.6),4.17-4.33(3H,m),4.50-4.60(1H,m),5.11(2H,s),5.20-5.26(1H,m),5.33(1H,s),7.36(5H,s).

The title compound(54B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:71%.

¹ H NMR(DMSO-d₆,δ):0.95-0.99(6H,m),2.16-2.22(1H,m),2.76-2.86(2H,m),3.32-3.40(1H,m),3.84-4.32(4H,m),4.57-4.60(1H,m),5.35(1H,d,2.6),8.54(3H,br.s).

IR(Nujol,cm⁻¹):1778,1742,1683,1646.

EXAMPLE 55(3RS,5SR)-3-[L-2-(N-Benzyloxycarbonylaminoacetyl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(55A) and(3RS,5SR)-3-[L-2-(N-Aminoacetyl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride (55B)

According to the similar method described as in example 40, N-protectedtitle compound(55A) was obtained as oil.

Yield:81%.

¹ H NMR(CDCl₃,δ):0.93(3H,d,J=6.8),0.95(3H,d,J=6.8),2.05-2.28(1H,m),2.74-2.90(2H,m),3.30(1H,dd,J=16.1,2.4),3.83-4.05(3H,m),4.12-4.35 (²H,m),4.48-4.66(2H,m),5.11(2H,s),5.34-5.47(2H,br.s),6.50(1H,d,J=8.0),7.35(5H,s).

IR(Nujol,cm⁻¹):3345,1784,1740,1680.

The title compound(55B) was obtained after deprotection as described inexample 40, followed by salt formation.

Yield:48%.

¹ H NMR(DMSO-d₆,δ):0.93(6H,d,J=6.6),2.04-2.14(1H,m),2.76-2.83(2H,m),3.32-3.40(1H,m),3.63-4.31(6H,m),4.54-4.59(1H,m),5.33(1H,dd,J=7.0,2.5),8.82(3H,br.s),8.86 (1H br,s).

IR(Nujol,cm⁻¹):3185,1779,1735,1681.

EXAMPLE 56(3RS,5SR)-3-[L-2-N-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(56A)and(3RS,5SR)-3-[L-2-N-(L-2-Amino-3-methylbutyryl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo-[3.2.0]heptan-7-onehydrochloride(56B)

According to the similar method described in example 41, protected titlecompound(56A) was obtained.

Yield:77%.

¹ H NMR(CDCl₃,δ):0.89-0.98(12H,m),2.06-2.21(2H,m),2.73-2.88(2H,m),3.29(1H,d,J=16.2),3.93-4.25(4H,m),4.52-4.59(2H,m),5.11(2H,s),5.33(1H,d,J=2.8),5.45(1H,d,J=8.8),6.54(1H,d,J=8.4),7.34(5H,s).

The title compound(56B) was obtained after deprotection as described inexample 40, followed by salt formation.

Yield:64%.

¹ H NMR(DMSO-d₆ δ):0.94-1.00(12H,d,J=6.7),2.10-2.20(2H,m),2.71-2.84(2H,m),3.32-3.40(2H,m),3.80-3.90(2H,m),4.15-4.23(3H,m),4.50-4.10(1H,m),5.34(1H,d,J=2.8),8.33(3H,br.s),8.75(1H,d,J=7.1).

IR(Nujol,cm⁻¹):3325,3200,1793,1762,1741,1685,1653.

EXAMPLE 57(3RS,5RS)-3-N-[L-2-N-(L-2-N-Benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(57A)and(3RS,5RS)-3-N-[L-2-N-(L-2-Amino-3-carboxypropanoyl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(57B)

According to the similar method as described in example 46, protectedtitle compound(57A) was obtained.

Yield:89%.

¹ H NMR(CDCl₃,δ):0.90(6H,t,J=7.2),2.12-2.18(1H,m),2.69-2.88(3H,m),3.08(1H,dd,J=4.2,17.4),3.29(1H,d,J=16.4),3.92-4.07(1H,m),4.10-4.25(2H,m),4.43-4.62(3H,m),5.13(4H,s),5.30-5.34(1H,m),5.97-6.04(1H,br.d),6.95-7.04(1H,br.d),7.35(10H,d,J=3.0).

IR(Nujol,cm⁻¹):3425,1783,1737,1679.

According to the similar method described as in example 46,the titlecompound(57B) was obtained as solid.

Yield:72%.

m.p.190° C.(dec.).

1H NMR(DMSO-d₆,δ):0.90(6H,d,J=6.3),2.0-2.40(2H,m),2.68-2.85(2H,m),3.16(1H,s),3.25-3.39(1H,m),3.63-3.90(2H,m),4.08-4.26(3H,m),4.48-4.58(1H,m),5.32(1H,s),8.63-8.75(1H,m).

IR(Nujol,cm⁻¹):1783,1742.

EXAMPLE 58(3RS,5RS)-3-N-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(58A) and(3RS,5RS)-3-N-(L-2-Amino-3-methylbutyryl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(58B)

According to the same procedure described in example 43, N-protectedtitle compound(58A) was obtained as solid.

Yield:44%.

¹ H NMR(CDCl₃,δ):0.97(6H,d,J=7.0),2.15(1H,q,J=6.8),2.58-2.70(1H,m),2.82(1H,d,J=16.6),3.28(1H,d,J=16.3),3.34-3.62(2H,m),3.36-4.01(2H,m),4.25-4.41(1H,m),5.12(2H,d,J=1.4),5.28(1H,d,J=2.5),5.25(1H,br.s),6.19(1H,br.s),7.36(5H,s).

IR(Nujol,cm⁻¹):3295,1781,1684,1646,1532.

The title compound(58B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:57%.

¹ H NMR(DMSO-d₆,δ):0.93(6H,d,J=6.8),2.00-2.16(1H,m),2.64-2.69(1H,m),2.79(1H,dd,J=3.7,16.6),3.29-3.50(4H,m),3.60(1H,d,J=4.8),3.77-3.88(1H,m),4.27-4.42(1H,m),5.34(1H,s),8.18(2H,br.s),8.68-8.81(1H,m).

IR(Nujol,cm-1):3350,3225,1716,1670.

EXAMPLE 59(3RS,5RS)-3-N-(D-2-N-Benzyloxycarbonylamino-3-methylbutyryl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(59A) and(3RS,5RS)-3-N-(D-2-Amino-3-methylbutyryl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(59B)

According to the same procedure described in example 43, N-protectedtitle compound(59A) was obtained as solid.

Yield:55%.

m.p.:141-143° C.

¹ H NMR(CDCl₃,δ):0.91-0.99(6H,m),2.15(1H,q,J=6.4),2.59-2.72(1H,m),2.82(1H,d,J=16.3),3.28(1H,d,J=16.3),3.36-3.62(2H,m),3.39-4.00(2H,m),4.28-4.41(1H,m),5.12(2H,s),5.25(1H,d,J=2.6),5.31(1H,br.s),6.20(1H,br.s),7.36(5H,s).

The title compound(59B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:31%.

¹ H NMR(DMSO-d₆,δ):0.93(6H,d,J=6.8),2.00-2.16(1H,m),2.64-2.69(1H,m),2.79(1H,dd,J=3.7,16.6),3.29-3.50(4H,m),3.60(1H,d,J=4.8),3.77-3.88(1H,m),4.27-4.42(1H,m),5.34(1H,s),8.18(2H,br.s),8.68-8.81(1H,m).

IR(Nujol,cm-1):3350,3225,1716,1670.

EXAMPLE 60(3RS,5SR)-3-(D-2-Benzyloxycarbonylamino-3-methylbutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(60A)and(3RS,5SR)-3-(D-2-Amino-3-methylbutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(60B)

According to the same procedure described in example 43, N-protectedtitle compound(60A) was obtained.

Yield:85%.

¹ H NMR(CDCl₃,δ):0.91(3H,d,J=6.9),0.99(3H,d,J=6.9),2.10-2.22(1H,m),2.79-2.89(2H,m),3.27(1H,d,J=16.1),3.93-4.33(3H,m),4.51-4.56(1H,m),5.11(2H,s),5.24(1H,d,J=9.0),5.32(1H,d,J=2.6),7.35(5H,s).

The title compound(60B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:70%.

¹ H NMR(DMSO-d₆,δ):0.88-0.96(6H,m),2.09-2.15(1H,m),2.68-2.96(2H,m),3.27-3.40(1H,m),3.77-4.24(4H,m),4.30-4.53(1H,m),5.28(1H,d,J=2.6),8.46(3H,br.s).

IR(Nujol,cm-1):3255,1781,1748,1685.

EXAMPLE 61(3RS,5SR)-3-(D-2-Acetylamino-3-methylbutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(61)

According to the same procedure described in example 44, titlecompound(61) was obtained.

Yield:49%.

¹ H NMR(DMSO-d₆,δ):0.90(6H,m),2.05(3H,s),3.10-3.15(1H,m),2.75-2.90(2H,m),3.30(1H,d,J=16.2),3.90-4.15(6H,m),5.35(1H,d,J=2.6),5.92(1H,d,J=2.5).

IR(Nujol,cm⁻¹):3315,2945,1794,1743,1665.

EXAMPLE 62(3RS,5SR)-3-[D-2-N-(D-2-N-Benzyloxycarbonylamino-3-methylbutyryl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(62A)and(3RS,5SR)-3-[D-2-N-(D-2-Amino-3-methylbutyryl)amino-3-methylbutyryl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(62B)

According to the same procedure described in example 41, N-protectedtitle compound(62A) was obtained.

Yield:70%.

¹ H NMR(CDCl₃,δ):0.92-0.99(12H,m),2.09-2.22(2H,m),2.74-2.89(2H,m),3.30(1H,J=16.2),3.94-4.24(4H,m),4.52-4.59(2H,m),5.12(2H,s),5.33(2H,m),6.36(1H,d,J=8.5),7.34(5H,s).

The title compound(62B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield: 58%.

¹ H NMR(DMSO-d₆,δ):0.96(12H,d,J=6.7),2.06-2.16(2H,m),2.71-2.82(2H,m),3.38-3.39(2H,m),3.78-3.89(2H,m),4.17-4.23(3H,m),4.51-4.55(1H,m),5.34(1H,d,J=2.8),8.33(3H,br.s),8.73(1H,d,J=7.1).

IR(Nujol,cm⁻¹):3355,3215,1784,1748,1681,1654.

EXAMPLE 63(3RS,5RS)-3-N-(L-2-N-Benzyloxycarbonylamino-3-phenylpropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(63A)and(3RS,5RS)-3-N-(L-2-Amino-3-phenylpropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(63B)

According to the same procedure described in example 43, N-protectedtitle compound(63A) was obtained as white solid.

Yield:55%.

m.p.:149-151° C.

¹ H NMR(CDCl₃,δ):2.44(1H,dd,J=7.3,11.7),2.56(1H,dd,J=7.2,11.9),2.76(1H,d,J=16.7),2.96-3.37(4H,m),3.77-3.90(1H,m),4.10-4.30(1H,m),4.31-4.43(1H,m),5.04(1H,d,J=2.6),5.09(2H,s),5.18(1H,d,J=2.6),5.28(1H,br.s),5.98(1H,br.s),7.27-7.35(5H,m).

IR(Nujol,cm⁻¹):3315,1783,1681,1665.

The title compound(63B) was obtained after deprotection as described inexample 43, followed by salt formation.

m.p.:220-233° C.(dec.).

¹ H NMR(DMSO-d₆,δ):2.45(1H,dd,J=6.7,11.8),2.62(1H,dd,J=6.7,11.6),2.76(1H,d,J=16.3),3.06-3.39(10H,m),3.59-3.78(2H,m),4.04(1H,br.t,J=6.7),4.17-4.18(1H,m),5.22(1H,d,J=2.3),5.28(1H,d,J=2.4),7.22-7.36(10H,m),8.37(4H,br.s),8.74(2H,m).

IR(Nujol,cm⁻¹):3205,1776,1561.

EXAMPLE 64 (3RS,5RS)-3-N-[L-2-N-(L-2-N-Benzyloxycarbonylamino-3-carboxypropanoyl)amino-3-phenylpropanoyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(64A)and(3RS,5RS)-3-N-[L-2-N-(L-2-Amino-3-carboxypropanoyl)amino-3-phenylpropanoyl]aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(64B)

A mixture of compound63B, obtained in example 63 (500 mg),3-N-Benzyloxycarbonylamino-3-benzyloxycarbonylpropanoic acid(822 mg),1,3-Dicyclohexyl-carbidiimide (475 mg), Triethylamine(0.35 ml) inDichloromethane(20 ml) was stirred at room temperature for 2 hrs.Resulted mixture was loaded on silicagel column, eluted withHexane-Ethyl acetate(1:2-1:3) and protected dipeptide(64A) was obtainedas solid.

Yield:51%.

¹ H NMR(CDCl₃,δ):2.44-2.61(1H,m),2.76(1H,d,J=16.4),2.90-3.12(3H,m),3.20(1H,dd,J=2.7,16.3),3.33(2H,t,J=5.3),3.77-3.88(1H,m),4.19-4.23(1H,m),4.52-4.61(1H,m),5.08(2H,s),5.10(2H,s),5.20(1H,d,J=2.6),5.71(1H,br.s),6.27(1H,br.s),6.79(1H,br.d,J=7.7),7.16-7.36(10H,m).

IR(Nujol,cm⁻¹):3285,1782,1730,1693.

The protected compound, obtained above, was deprotected as in example 46and the title compound(64B) was obtained as solid.

¹ HNMR(DMSO-d₆,δ):1.70-1.96(1H,m),2.19-2.36(1H,m),2.67(1H,dd,J=6.4,11.5),2.78(1H,d,J=17.1),3.04-3.45(3H,m),3.12(1H,dd,J=2.9,16.5),3.78(1H,dd,J=6.5,11.5),4.23-4.47(1H,m),5.31(1H,d,J=2.6),6.72(2H,br.s),8.35(1H,br.s).

IR(Nujol,cm⁻¹):3300,1782.

EXAMPLE 65 (3RS,5SR)-3-(L-3-N-Benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(65A) and(3RS,5SR)-3-(L-3-Amino-3-carboxypropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(65B)

A mixture of(3RS,5SR)-3-Bromomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(1.0 g),(3-N-Benzyloxycarbonylamino-3-benzyloxycarbonyl)propanoic acid(2.5 g),Cesium carbonate (1.63 g) and Hexamethylphosphoric triamide(10 ml) washeated with stirring at 60-70° C. for 16 hrs. The reaction mixture wasthen diluted with Ethyl acetate, washed with water, brine and dried overMagnesium sulfate. The residual oil after removal of solvent in vacuo,was purified by silicagel column chromatography eluted with Hexane-Ethylacetate (1:1). The desired title compound(65A) was obtained as oil.

Yield:86%.

¹ H NMR(CDCl₃,δ):2.62-3.26(5H,m),3.83-4.20(3H,m),4.36-4.46(1H,m),4.66-4.75(1H,m),5.10(2H,s),5.16(2H,s),5.23-5.26(1H,m),5.74-5.84(1H,m),7.30(10H,s).

IR(Nujol,cm⁻¹):3355,2965,1787,1745.

The protected ester, obtained above, was deprotected as described inexample 46 and the title compound(65B) was obtained as solid.

Yield:69%.

m.p.:175° C.

¹ H NMR(DMSO-d₆,δ):2.57-3.00(4H,m),3.23-3.70(2H,m),3.83-3.98(1H,m),4.13-4.25(2H,m),4.53-6.67(1H,m),5.39(1H,d,J=2.5).

IR(Nujol,cm⁻¹):3130,1793,1736.

EXAMPLE 66 (3RS,5SR)-3-(L-2-N-Benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(66A) and(3RS,5SR)-3-(L-2-Amino-3-carboxypropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(66B)

According to the same procedure described in example 65, protected titlecompound(66A) was obtained.

Yield:74%.

¹ H NMR(CDCl₃,δ):2.68-2.88(1H,m),2.79(1H,dd,J=3.4,16.5),2.90-3.10(1H,m),3.19(1H,d,J=16.3),3.84-3.96(1H,m),4.17-4.22(2H,m),4.41-4.56(1H,m),4.62-4.77(1H,m),5.12(4H,s),5.26(1H,d,J=2.6),5.74(1H,br.d),7.34(5H,s),7.36(5H,s).

IR(Neat,cm⁻¹):3355,1781,1753,1731,1518.

The protected compound, obtained above, was deprotected as described inexample 46 and the title compound(66B) was obtained as solid.

Yield:55%.

m.p.:150-180° C.(dec.).

¹ H NMR(DMSO-d₆,δ):2.77-2.84(1H,m),2.91(1H,dd,J=4.3,11.2),2.94(1H,d,J=16.7),3.40(1H,dd,J=1.6,19.6),4.05(1H,dd,J=7.0,11.9),4.28-4.52(3H,m),4.70-4.79(1H,m),5.46(1H,d,J=2.4).

IR(Nujol,cm⁻¹):3375,1776,1752.

EXAMPLE 67(3RS,5RS)-3-N-(L-2-N-Benzyloxycarbonylamino-3-benzyloxycarbonylpropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(67A) and(3RS,5RS)-3-N-(L-2-Amino-3-carboxypropanoyl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(67B)

(3RS,5RS)-3-Azidomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one, (1.0 g),was hydrogenated by using 10% Palladium on activated carbon(250 mg) at50 psi for 1 hr. After removal of catalyst,L-(2-N-Benzyloxycarbonylamino-3-benzyloxycarbonyl)propanoic acid (2.55g), and Triethylamine (0.1 ml) was added to the filtrate, followed bydropwise addition of a solution of 1,3-Dicyclohexylcarbodiimide (1.47 g)in Ethyl acetate(10 ml) under ice-cooled condition. After 1 hr stirring,the reaction mixture was loaded on silicagel column and eluted withHexane-Ethyl acetate(2:3). The desired protected amide derivative(67A)was obtained as oil.

Yield: 50%.

¹ H NMR(CDCl₃,δ):2.56-2.71(1H,m),2.81(1H,d,J=16.7),3.06-3.18(1H,m),3.26(1H,dd,J=2.8,16.4),3.36-3.52(2H,m),3.83-3.94(1H,m),4.23-4.37(1H,m),4.50-4.64(1H,m),5.13(4H,d,J=2.8),5.24-5.29(1H,m),5.90(1H,br,d),6.71(1H,br,s),7.34(5H,s),7.36(5H,s).

IR(Neat,cm⁻¹):3330,1778,1727,1667,1529.

The protected amido derivative obtained above was deprotected asdescribed in example 46 and the title compound(67B) was obtained assolid.

Yield:74%.

m.p.275-285° C.(dec.).

¹ H NMR(DMSO-d₆,δ):2.65-2.86(3H,m),2.93(1H,d,J=17.2),4.40(1H,dd,J=2.2,16.7),3.47-3.55(2H,m),4.00(1H,dd,J=6.6,11.9),4.23(1H,dd,J=5.6,7.4),4.51-4.56(1H,m),5.43(1H,d,J=2.6).

IR(Nujol,cm⁻¹):3215,1677,1562.

EXAMPLE 68 (3RS,5SR)-3-(D-4-N-Benzyloxycarbonylamino-4-benzyloxycarbonylbutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(68A) and(3RS,5SR)-3-(D-4-Amino-4-carboxybutyryl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(68B)

According to the same procedure as example 65, protected titlecompound(68A) was obtained as oil.

Yield:48%.

¹ H NMR(CDCl₃,δ):1.97-2.19(1H,m),2.17-2.30(1H,m),2.40-2.50(2H,m),2.73(1H,dd,J=6.1,11.6),3.25(1H,d,J=16.2),3.94(1H,dd,J=6.9,11.6),4.05-4.20(2H,m),4.40-4.55(2H,m),5.10(2H,m),5.17(2H,m),5.30(1H,t,J=2.8),5.39(br.s),7.35(10H,s).

IR(Neat,cm⁻¹):3355,1784,1739,1525.

The protected ester derivative obtained above was deprotected asdescribed in example 46 and the title compound(68B) was obtained assolid.

Yield:82%.

m.p.:>250° C.(dec.).

¹ H NMR(DMSO-d₆,δ):1.90-2.04(2H,m),2.75(1H,dd,J=5.9,16.4),2.50-2.57(2H,m),2.80(1H,d,J=16.4),3.33(1H,dd,J=2.6,16.2),3.84(1H,dd,J=7.1,11.6),4.12(2H,d,J=3.4),4.52-4.60(1H,m),5.32(1H,d,J=2.5).

EXAMPLE 69(3RS,5RS)-3-N-(D-4-N-Benzyloxycarbonylamino-4-benzyloxycarbonylbutyryl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(69A) and(3RS,5RS)-3-N-(D-4-Amino-4-carboxybutyryl)aminomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(69B)

According to the same procedure as example 67, protected titlecompound(69A) was obtained as solid.

Yield:22%.

¹ H NMR(CDCl₃,δ):1.90-2.10(1H,m),2.11-2.35(3H,m),2.60-2.72(1H,m),2.81(1H,d,J=16.2),3.20-3.60(3H,m),3.92(1H,dd,J=7.4,12.0),4.30-4.50(1H,m),5.11(2H,s),5.17(2H,s),5.30(1H,s),5.59(1H,br.s),6.16(1H,br.s),7.35(10H,s).

IR(Neat,cm⁻¹):3345,1783,1720,1654,1533.

The protected amido derivative obtained above was deprotected asdescribed in example 46 and the title compound(69B) was obtained assolid.

Yield:48%.

¹ HNMR(DMSO-d₆,δ):1.74-1.83(1H,m),1.84-1.93(1H,m),2.26(2H,t,J=7.9),2.67(1H,dd,J=6.4,11.5),2.77(1H,d,J=16.3),3.13-3.18(1H,m),3.19-3.22(1H,m),3.25-3.33(1H,m),3.32(1H,dd,J=2.7,16.3),3.77(1H,dd,J=6.6, 11.6),4.28-4.34(1H,m),5.31(1H,d,J=2.9),7,30(1H,br.s),8.33(1H.br,s).

EXAMPLE 70(3RS,5SR)-3-(L-2-N-Benzyloxycarbonylamino-3-hydroxypropanyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(70)

780 mg (3.8 mmol) of(3RS,5SR)-3-Bromomethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one and 1.0 gof sodium salt of L-(2-N-Benzyloxycarbonylamino-3-hydroxy)propanoic acidin 0.8 ml of Hexamethylphosphoric triamide was heated at 65° C. for 3hrs. General work-up and purification gave the title compound as oil.

Yield:64%.

¹ H NMR(CDCl ₃,δ):2.19-2.32(1H,m),2.75-2.87(2H,m),3.21-3.32(1H,dd,J=2.6,13.6),3.92-4.55(7H, m),5.13 (2H,s),5.32(H,s),5.66-5.74 (1H, m)7.34 (5H, s).

IR(Nujol,cm⁻¹):3430,2963,1780,1751.

EXAMPLE 71(3RS,5SR)-3-[L-2-N-(D-2-N-Benzyloxycarbonylaminopropanoyl)amino-3-hydroxypropanoyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(71)

600 mg (1.65 mmol) of compound(70) and 450 mg of 10% Palladium onactivated carbon in 20 ml Ethyl acetate was shaken under Hydrogenatmosphere for 1 hr and filtered through celite. To the filtrate 370 mg(1.6 mmol) of D-2-(N-Benzyloxy-carbonyl)amino propanoic acid and 170 mg(0.80 mmol) of 1,3-Dicyclohexylcarbodiimide were added under cooling andstirred at room temperature for 3 hrs. The solid was removed byfiltration and the solution was concentrated. The residue was purifiedby flash column using Ethyl acetate-Hexane(4:1) as eluent. The titlecompound(71) was obtained as solid.

Yield:3%.

m.p.: 150-155° C.

¹ H NMR(CDCl₃,δ):1.41(3H,d,J=7.0),2.38(1H,s),2.77-2.90(2H,m),3.27(1H,dd,J=2.3,11.5),3.85-4.57(8H,m),5.12(2H,s),5.34(1H,s),5.95(1H,d,J=7.2),7.35(5H,s),7.56(1H,J=7.6).

EXAMPLE 72(3RS,5SR)-3-L-(2-N-Benzyloxycarbonylamino-3-benzyloxypropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(72)

According to the same procedure as example 61, the title compound (72)was obtained as oil.

Yield:94%.

¹ H NMR(CDCl₃,δ):2.70-2.82(2H,m),3.14-3.22(1H,m),3.66-3.74(1H,m),3.84-3.95(2H,m),4.16-4.33(2H,m),4.44-4.58(4H,m),5.12(2H,s),5.24(1H,dd,J=2.3,6.7),5.62(1H,d,J=4.5),7.25-7.36(10H,m).

IR(Neat,cm⁻¹):3345,1781,1718.

EXAMPLE 73(3RS,5R)-3-[L-2-N-(D-2-N-Benzyloxycarbonylaminopropanoyl)amino-3-benzyloxypropanoyl]oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(73)

According to the same procedure as example 41, the title compound (73)was obtained as solid.

Yield:34%.

m.p.:107-108° C.

¹ H NMR(CDCl₃,δ):1.48(3H,d,J=2.8),2.68-2.80(2H,m),3.14-3.22(1H,m),3.60-3.70(1H,m),3.85-3.94(2H,m),4.04-4.55(6H,m),4.70-4.78(1H,m),5.10(2H,s),5.25(1H,dd,J=2.3,6.8),5.30-5.38(1H,m),6.85-6.92(1H,m),7.25-7.34(10H,m).

IR(Nujol,cm⁻¹):3315,1780.

EXAMPLE 74(3RS,5SR)-3-[L-2-N-(L-2-N-Benzyloxycarbonylamino-3-methylbutyryl)amino-3-benzyloxypropanoyloxymethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(74A) and(3RS,5SR)-3-[L-2-N-(L-2-N-Amino-3-methylbutyryl)amino-3-benzyloxypropanoyloxymethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(74B)

According to the same procedure as example 41, protected titlecompound(74A) was obtained as solid.

Yield:51%.

m.p.:100-102° C.

¹ HNMR(CDCl₃,δ):0.90-0.95(3H,d,J=3.0),0.95-1.04(3H,d,J=2.8),2.10-2.18(1H,m),2.67-2.82(2H,m),3.17-3.27(1H,m),3.62-3.68(1H,m),3.86-3.96(2H,m),4.05-4.26(3H,m),4.42-4.56(3H,m),4.72-4.78(1H,m),5.13(2H,s),5.23.(H,dd,J=2.4,16.2),5.34(1H,d,J=4.5),6.58(1H,d,J=4.4),7.25-7.36(10H,m).

IR(Nujol,cm⁻¹):3320,2970,1781.

The title compound(74B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:77%.

m.p.:168° C. (dec).

¹ H NMR(DMSO-d₆,δ):0.98-1.18 (6H,m), 2.12-2.22(1H,m) 2.72-2.86(2H,m),3.28-3.34(1H,m),3.68-3.94(4H,m),4.20-4.28(2H,m),4.52-4.77(4H,m), 5.34(H,dd,J=2.5,16.2),7.40(5H,s),8.24-8.32 (3H,s),9.06 (1H,d, J=8.1).

IR(Nujol,cm⁻¹):3335,1772,1678.

EXAMPLE 75(3RS,5SR)-3-(L-2-Acetamido-3-hydroxypropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.20]heptan-7-one(75A)and(3RS,5SR)-3-(2-Acetamido-3-acetoxypropanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(75B)

500 mg (1.3 mmol) of the compound 72 was deprotected as usual manner. Tothis 140 mg (1.37 mmol) of Triethylamine was added and cooled to 0° C.110 mg (1.37 mmol) Acetyl chloride was added, stirred at the sametemperature for 1 hr followed by at room temperature for 1 hr. Thesolution was filtered and the filtrate was concentrated. The compoundwas purified over silica gel using Ethyl acetate first and then Ethylacetate-Acetone (5:1). Two fractions were collected. N-Acetylcompound(75A) and N,O-diacetyl compound(75B) were obtained.

Monoacetyl compound(75A):

Yield:39%.

¹ HNMR(CDCl₃,δ):2.07(6H,s),2.75-2.90(2H,m),3.25-3.38(1H,m),3.95-4.07(1H,m),4.24-4.36(3H,m),4.50-4.60(2H,m),4.84-4.92(1H,m),5.34(1H,d,J=2.5),6.20-6.30(1H,m).

IR(Nujol,cm⁻¹):3335,2960,1779,1664.

Diacetyl compound(75B):

Yield:26%.

hu 1HNMR(CDCl₃,δ):2.08(3H,s),2.44(1H,t,J=6.9),2.77-2.90(2H,m),3.30(1H,dd,J=2.8,12.2),3.95-4.40(5H,m),4.54-4.64(1H,m),4.70-4.78(1H,m),5.36(1H,d,J=2.6),6.38-6.46(1H,m).

IR(Neat,cm⁻¹):3360,2968,1774,1653.

EXAMPLE 76(3RS,5RS)-3-[N-(L-2-N-Benzyloxycarbonylamino-3-hydroxypropanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(76A) and(3RS,5RS)-3-[N-(L-2-Amino-3-hydroxypropanoyl)aminomethyl]-4-oxa-1-azabicyclo[3.2.0]heptan-7-onehydrochloride(76B)

According to the same procedure described in example 43, N-protectedtitle compound(76A) was obtained as white solid.

Yield:38%.

m.p.:114-116,124.5-137° C.

¹ H NMR(CDCl₃,δ):2.69(1H,dd,J=6.3,11.0,),2.81(1H,d,J=15.8),3.25(1H,d,J=16.3),3.47(2H,t,J=5.3),3.62-3.77(1H,m),3.85-3.47(3H,m),4.17-4.30(1H,m),4.30-4.43(1H,m),5.13(2H,s),5.28-5.31(1H,m),6.11-6.21(1H,m),7.10(1H,br.s),7.36(5H,s).

IR(Nujol,cm⁻¹):3280,1772,1683,1554,1457.

The title compound(76B) was obtained after deprotection as described inexample 43, followed by salt formation.

Yield:38%.

¹ H NMR(D₂ O,δ):2.72-2.88(1H,m),2.91(1H,d,J=13.3),3.39(1H,dd,J=2.6,16.3),3.50(2H,d,J=5.3),3.70-4.20(4H,m),4.462H,m),5.46(1H,d, J=2.6).

IR(Nujol,cm⁻¹):3360,3325,1766,1679,1630.

EXAMPLE 77(3RS,5SR)-3-(L-2,6-N-Dibenzyloxycarbonylaminohexanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(77A)and(3RS,5SR)-3-(L-2,6-Diacetamidohexanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(77B)

According to the same procedure described in example 40,(2,6-Dibenzyloxycarbonylamino)hexanoyloxy derivative(77A) was obtainedas thick oil.

Yield:76%.

¹ H NMR(CDCl₃,δ):1.42-1.80(6H,m),2.73-2.86(2H,m),3.18-3.30(3H,m),3.91-4.52(5H,m),4386-5340(7H,m),7.33(10H,s).

IR(Neat,cm⁻¹):3355,3070,2960,1781,1751,1721.

To a solution of (2,6-Dibenzyloxycarbonylamino)hexanoyloxyderivative(77A) obtained above (1.8 g,3.33 mmol) and Acetic anhydride(3.2 ml,3.33 mmol) in Ethyl acetate (100 ml) was added Palladium onactivated carbon (10%,53.8% moist,2.0 g) and the mixture washydrogenolysed at 50 psi for 2 hr. The catalyst was filtered off over apad of celite and the solution was concentrated. Purification on asilica gel column using Ethyl acetate-acetone (1:2:5) as the eluent gavea thick oil(77B).

Yield:63%.

¹ H NMR(CDCl₃,δ):1.19-1.87(6H,m),1.98(3H,s),2.04(3H,s),2.76-2.89(2H,m),3.14-3.34(3H,m),3.98(1H,dd,J=11.6,7.0),4.10-4.25(2H,m),4.47-4.58(2H,m),5.36(1H,br.s),5.89(1H,br.t),6.49(1H,d,J=7.0).

IR(Neat,cm⁻¹):3320,3075,2693,1784,1762,1741,1656.

EXAMPLE 78(3RS,5SR)-3-(L-5-acetamide-2-N-Benzyloxycarbonylaminohexanoyl)oxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(78)

To a Ethyl acetate(60 ml) solution of 2,5-dibenzyloxycarbonylaminohexanoyloxy derivative (77A), (1.0 g,1.85 mmol) was added Palladium onactivated carbon (10%,1.0 g) and the mixture was hydrogenolysed at 50psi for 2 h. The mixture was filtered through a pad of celite and cooledin an ice-bath. Acetic anhydride (0.44 ml,4.66 mmol) and Triethylamine(0.77 ml) were added and the mixture was stirred for 2 h and washed withwater (60 ml) and brine. The Ethyl acetate solution was dried overMagnesium sulfate, concentrated and passed through a silica gel columnchromatography using Ethyl acetate as the eluent to give an oil(78).

Yield:12%.

¹ HNMR(CDCl₃,δ):1.29-1.89(6H,m),2.01(3H,s),2.72-2.88(2H,m),3.14-3.31(3H,m),3.96(1H,dd,J=11.6,6.9),4.13-4.29(2H,m),4.53-4.56(2H,m),4.97(1H,br.t),5.09(2H,s),5.32(1H,br.s),6.29(1H,d,J=7.0),7.34(5H,s).

IR(Nujol,cm⁻¹):3335,2950,1783,1740,1717,1659.

EXAMPLE 79(3RS,5SR)-3-(L-2-N-Benzyloxycarbonylamino-3-phenylpropanoyloxymethyl-4-oxa-1-azabicyclo[3.2.0]heptan-7-one(79)

According to the same procedure described in example 43, N-protectedtitle compound(79) was obtained.

Yield:63%.

¹ H NMR(CDCl₃,δ):2.57-2.74(1H,m),2.82(1H,d,J=16.2),3.11(2H,d,J=6.1),3.25(1H,dd,J=2.3,16.0),3.83-3.95(1H,m),4.12-4.23(2H,m),4.40-4.55(1H,m),4.59-4.75(1H,m),5.10(2H,s),5.12-5.27(2H,m),7.20-7.38(10H,m).

IR(Neat,cm-1):3335,1784,1747,1722.

TEST EXAMPLE 1 In Vitro KB Cell Cytotoxicity Assay

In vitro KB cell cytoxocity assay was done by modification of thecrystal violet assay (Grillis et al., Anal Biochem., 159, 109-113(1986).

KB cells were cultivated in Eagles minimum essential medium supplementedwith 10% calf serum and incubated at 37° C. in a humidified 5% CO₂atmosphere to prepare a cell stock. Cells were counted using a neubauerhemocytometer and seeded in 96 well plates at 100 μl of 3×10⁴ cells/mland cultured for one day. Test compounds were diluted and 100 μl of thesolution was added in triplicate wells to give final concentration of10, 5, 1, 0.5, 0.1, 0.05 and 0.01 μg/ml. Control wells were identicalexcept that test compound was absent. These were cultured for threedays. Then the cells were fixed with addition of 20 μl of 25%glutaraldehyde for 15 minutes, washed with water and dried. Then stainedwith 100 μl of 0.05% crystal violet for 15 minutes, washed with waterand dried. The wells are eluted with 1001 of 0.05M NaH₂ PO₄ /ethanol(1:1 v/v) and read at OD₅₄₀ on a multiscan spectrophotometer. Inhibitionvalue of cell growth was calculated based on optical density using thefollowing equation; ##EQU1##

TD₅₀ values were calculated from linear regression ines of the log-logitplot.

The compound of formula (I) was assayed by this method against KB celllines and their TD₅₀ values are reported in Table 1.

TEST EXAMPLE 2 In Vitro L1210 and P388 Cell Cytotoxicity Assay

In vitro :L1210 and P388 cell cytotoxicity assay was done by the methodof microculture tetrazolium assay (Alley et al., Cancer Research, 48,589-601 (1988).

L1210 and P388 cells were cultivated in RPMI 1640 medium supplementedwith 10% fetal calf serum and 50 μl of 2-mercaptoethanol at 37° C. inhumidified 5% CO₂ atmosphere to prepare a cell stock. Cells were countedusing neubauer hemocytometer and seed in 96 well plates at 100 μl of0.5×10⁴ cells per ml. The test compounds were diluted and 100 μl of thesolution was added in triplicate wells to give the final concentrationof 10, 5, 1, 0.5, 0.1, 0.05 and 0.01 μg/ml. Control wells were identicalexcept that the test compound was absent. These were cultured for threedays. Results were assayed using the microculture tetrazolium assaybriefly. 50 μl of MTT formazoan working solution (1:5 v/v in culturemedium) was added to each well and cultures were incubated at 37° C. for4 hrs. Culture plates were centrifuged at low speed for 5 minutes. Allbut 10-20 μl of culture medium supernatant was removed by slowaspiration and replaced by mechanical shaker and read at OD₅₄₀ on amultiscan spectrophotometer. Inhibition value of cell growth wascalculated based on optical density using the following equation;##EQU2##

TD₅₀ values were calculated from linear regression ines of the log-logitplot.

The compound of formula (I) was assayed by this method against L1210 andP388 cell lines and their TD₅₀ values are reported in Table 2.

                  TABLE 1                                                         ______________________________________                                        In Vitro Cell Toxicity of Compounds of                                          General Formula I                                                                                                KB Cell                                       Cytotoxicity                                                               Example No. X R TD.sub.50 μg/ml)                                         ______________________________________                                         1      NH     COCH.sub.3          0.263                                         2 NH COCH.sub.3 (3S, 5S) 0.77                                                 3 NH COCH.sub.3 (3R, 5R) 3.15                                                 4 NH CO(CH.sub.2).sub.4 CH.sub.3 0.312                                        5 NH COCH(CH.sub.3).sub.2 0.181                                               6 NH COC.sub.6 H.sub.11 (alicyclic) 0.073                                     7 NH COCF.sub.3 0.205                                                         8 NH COCH.sub.2 Cl 0.084                                                      9 NH COCH.sub.2 N.sub.3 0.296                                                10 NH COCH.sub.2 -triazole (1, 2, 3) 0.282                                    11 NH COCH.sub.2 OCHO 0.147                                                   12 NH COCH.sub.2 OH 0.125                                                     13 NH CO(CH.sub.2).sub.5 Br 0.491                                             14 NH CO(CH.sub.2).sub.5 OCHO 0.243                                           15 NH CO(CH.sub.2).sub.5 N.sub.3 0.254                                        16 NH CO(CH.sub.2).sub.5 -triazole (1, 2, 3) 0.318                            17 NH CO(CH.sub.2).sub.5 NHCOCH.sub.3 0.439                                   18 NH CO(CH.sub.2).sub.2 --COOH 2.85                                          19 NH CO(CH.sub.2).sub.2 --CH=CH.sub.2 0.266                                  20 NH COC≡CH 0.333                                                      21 NH COOCH.sub.2 C.sub.6 H.sub.5 0.340                                       22 NH H.HCl 0.344                                                             23 NH COC.sub.6 H.sub.5 0.088                                                 24 NH COC.sub.6 H.sub.4 OH (4) 0.276                                          25 NH COC.sub.6 H.sub.4 OCH.sub.3 (4) 0.255                                   26 NH COC.sub.6 H.sub.3 (OCH.sub.3).sub.2 (3, 4) 0.249                        27 NH COC.sub.6 H.sub.4 F (4) 0.24                                            28 NH COC.sub.6 H.sub.3 F.sub.2 (2, 5) 0.379                                  29 NH COC.sub.6 H.sub.2 F.sub.3 (2, 4, 5) 0.535                               30 NH COC.sub.6 H.sub.4 CN (4) 0.378                                          31 NH COCH.sub.2 -thiophene (2) 0.098                                         32 NH CO-pyridine (3) 0.78                                                    33 NH CON(C.sub.2 H.sub.5).sub.2 0.246                                        34 NH CONHCH.sub.2 clavam 0.151                                               35 NH SO.sub.2 CH.sub.3 0.198                                                 36 NH SO.sub.2 C.sub.6 H.sub.4 CH.sub.3 (4) 0.338                             37 NH SO.sub.2 C.sub.6 H.sub.4 Cl (4) 0.484                                   38 NH SO.sub.2 C.sub.6 H.sub.4 OCH.sub.3 (4) 0.158                            39 O COCH.sub.2 NH.sub.2.HCl 0.613                                            40B O COCH.sub.2 NHCOCH.sub.2 NH.sub.2.HCl 0.636                              41B O COCH.sub.2 NH-- 0.295                                                     (L)--COCH(CH.sub.3)NH.sub.2.HCl                                             42B O COCH.sub.2 NH--(L)-- 0.388                                                COCH[CH(CH.sub.3).sub.2 ]NH.sub.2.HCl                                       43 NH COCH.sub.2 NH.sub.2.HCl 0.429                                           44 NH COCH.sub.2 NHCOCH.sub.3 0.341                                           45B NH COCH.sub.2 NH--(L)-- 1.97                                                COCH[CH(CH.sub.3).sub.2 ]NH.sub.2.HCl                                       46B NH COCH.sub.2 NH--(L)-- 2.63                                                COCH(NH.sub.2)CH.sub.2 COOH                                                 48B O (L)COCH(CH.sub.3)NH.sub.2.HCl 0.878                                     49B O (L)COCH(CH.sub.3)NH--(L)-- 0.537                                          COCH[CH(CH.sub.3 (.sub.2 ]NH.sub.2.HCl                                      50B NH (L)COCH(CH.sub.3)NH.sub.2.HCl 0.657                                    51B O (D)COCH(CH.sub.3)NH.sub.2.HCl 0.867                                     52 O (D)COCH(CH.sub.3)NH--(D)--COCH-- 0.197                                     (CH.sub.3) NHCOCH.sub.2 -thiophene (2)                                      53B NH (D)COCH(CH.sub.3)NH.sub.2.HCl 0.316                                    54B O (L)COCH[CH(CH.sub.3).sub.2 ]NH.sub.2.HCl 1.9                            55B O (L)COCH[CH(CH.sub.3).sub.2 ]NH-- 0.522                                    COCH.sub.2 NH.sub.2.HCl                                                     56B O (L)COCH[CH(CH.sub.3).sub.2)NH-- 0.283                                     (L)--COCH[CH(CH.sub.3).sub.2 ]NH.sub.2.HCl                                  57B O (L)COCH[CH(CH.sub.3).sub.2 ]NH-- 1.54                                     (L)--COCH(NH.sub.2)CH.sub.2 COOH                                            60B O (D)COCH[CH(CH.sub.3).sub.2 ]NH.sub.2.HCl 0.903                          61 O (D)COCH[CH(CH.sub.3).sub.2 ]NHCOCH.sub.3 0.385                           62B O (D)COCH[CH(CH.sub.3).sub.2 ]NH-- 0.381                                    (D)--COCH[CH(CH.sub.3).sub.2 ]NH.sub.2 .HCl                                 63B NH (L)COCH(CH.sub.2 C.sub.6 H.sub.5)NH.sub.2.HCl 0.573                    64B NH (L)COCH(CH.sub.2 C.sub.6 H.sub.5)NH-- 2.65                               (L)--COCH(NH.sub.2)CH.sub.2 COOH                                            65B O (L)COCH.sub.2 CH(NH.sub.2)COOH 0.451                                    66B O (L)COCH(NH.sub.2)CH.sub.2 COOH 0.204                                    67B NH (L)COCH(NH.sub.2)CH.sub.2 COOH 6.04                                    68B O (D)CO(CH.sub.2).sub.2 CH(NH.sub.2)COOH 0.189                            69B NH (D)CO(CH.sub.2).sub.2 CH(NH.sub.2)COOH 2.47                            70 O (L)COCH(CH.sub.2 OH)NHZ 0.352                                            71 O (L)COCH(CH.sub.2 OH)NH-- 0.549                                             (D)--COCH(CH.sub.3)NHZ                                                      72 O (L)COCH(CH.sub.2 OCH.sub.2 C.sub.6 H.sub.5)NHZ 1.67                      73 O (L)COCH(CH.sub.2 OCH.sub.2 C.sub.6 H.sub.5)NH-- 2.22                       (D)--COCH(CH.sub.3)NHZ                                                      74B O (L)COCH(CH.sub.2 OCH.sub.2 C.sub.6 H.sub.5)NH-- 0.669                     (L)--COCH[CH(CH.sub.3).sub.2 ]NH.sub.2.HCl                                  75A O (L)COCH(CH.sub.2 OH)NHCOCH.sub.3 1.98                                   75B O (L)COCH(CH.sub.2 OCOCH.sub.3)NHCOCH.sub.3 0.567                         76B NH (L)COCH(CH.sub.2 OH)NH.sub.2.HCl 8.81                                  77A O (L)COCH(NHZ)(CH.sub.2).sub.4 NHZ 1.18                                   78 O (L)COCH(NHCOCH.sub.3)(CH.sub.2).sub.2 NHZ 3.38                         ______________________________________                                         Z;Benzyloxycarbonyl                                                      

                  TABLE 2                                                         ______________________________________                                        In Vitro Cell Toxicity of Compounds of General Formula I                        Against Sensitive and Resistant Tumor Cell Lines                                    Cell Toxicity (μg/ml)                                              Example No.                                                                           L-1210 (S) L-1210 (R)                                                                              P388 (S) P388 (R)                                ______________________________________                                        1       0.103       0.104    0.103    0.074                                     G0069A 2.17  1.87 1.02  0.751                                                 Adriamycin 0.004 0.36 0.003 0.575                                             Vincristine 0.002 0.20 2.95 × 10.sup.-7 0.279                         ______________________________________                                    

TEST EXAMPLE 3 In Vivo Antitumor Activity Against Sarcoma 180

The compounds of general formula (I) were tested in vivo against Sarcoma180 xenografted tumor to mice as illustrated herein after.

Sarcoma 180, 5×10⁶ cells were inoculated by S.C. to male ICR mice (6week old) on day 0. Drugs were administered on days 1, 5 and 9. Micewere killed and tumor weight was measured on day 12 aftertransplantation. The percentage inhibition of tumor growth wascalculated from the mean tumor weight of the treated group compared withthat of the control group. Number of mice used in each group was between6 to 7. The percentage inhibition of tumor Sarcoma 180 group by compoundof formula (I) are summarized in Table 3.

                  TABLE 3                                                         ______________________________________                                        Effect of Compounds of Formula (I) Against Sarcoma 180                          (s.c. - i.p.) in Male ICR                                                                 Dose         Mortality                                            Example No. (mg/kg/day) in 12 days % Inhibition                             ______________________________________                                         1        12.5         0/6      71.4                                             6.25 0/6 49.3                                                                 3.1 0/6 33.9                                                                  2 20 1/7 77.5                                                                 10 0/6 44.7                                                                   4 100 0/6 49.4                                                                6 80 0/6 43.3                                                                 40 0/6 35.7                                                                   20 0/6 32.1                                                                   7 100 2/6 39.8                                                                8 35 1/6 64.0                                                                 17.5 0/6 51.3                                                                 8.8 0/6 39.0                                                                 22 80 0/6 40.3                                                                 40 0/6 26.7                                                                  23 100 0/6 27.8                                                               31 40 1/6 35.5                                                                33 90 0/6 74.5                                                                 45 0/6 66.2                                                                   22.5 0/6 46.6                                                                34 25 5/6 92.5                                                                 12.5 0/6 76.3                                                                 6.25 0/6 59.8                                                                35 100 1/6 64.6                                                               38 100 1/6 72.0                                                                50 0/6 55.4                                                                   25 0/6 26.5                                                                  39 50 0/6 76.7                                                                 25 0/6 56.7                                                                   12.5 0/6 41.9                                                                 .sup. 40B 50 0/6 72.0                                                         25 0/6 54.0                                                                   12.5 0/6 48.3                                                                 .sup. 41B 25 0/6 62.8                                                         12.5 0/6 43.9                                                                 .sup. 42B 50 0/6 85.8                                                         25 0/6 69.0                                                                   12.5 0/6 49.9                                                                43 50 0/6 72.1                                                                 25 0/6 58.9                                                                   12.5 0/6 57.0                                                                 6.3 0/6 48.7                                                                 44 25 4/6 85.3                                                                 12.5 0/6 45.9                                                                 .sup. 45B 50 0/6 81.7                                                         25 0/6 39.3                                                                   .sup. 46B 50 1/6 76.9                                                         25 0/6 55.7                                                                   12.5 0/6 44.7                                                                 .sup. 48B 50 2/6 77.3                                                         25 0/6 66.8                                                                   12.5 0/6 44.9                                                                 .sup. 49B 50 0/6 71.0                                                         25 0/6 55.7                                                                   .sup. 51B 100 5/6 93.8                                                        50 0/6 82.4                                                                   25 0/6 50.6                                                                   12.5 0/6 40.9                                                                52 100 2/6 70.7                                                                50 0/6 63.9                                                                   25 0/6 45.2                                                                   .sup. 53B 25 1/6 73.8                                                         12.5 0/6 61.9                                                                 6.3 0/6 47.3                                                                  .sup. 54B 100 0/6 84.3                                                        50 0/6 53.8                                                                   25 0/6 28.5                                                                   .sup. 55B 50 0/6 74.4                                                         25 0/6 47.6                                                                   .sup. 56B 50 0/6 73.2                                                         25 0/6 69.2                                                                   12.5 0/6 48.9                                                                 .sup. 57B 50 1/6 83.1                                                         25 0/6 58.1                                                                   12.5 0/6 40.9                                                                 .sup. 60B 100 0/6 77.7                                                        50 0/6 49.8                                                                   .sup. 62B 100 0/6 42.1                                                        .sup. 63B 100 0/6 57.6                                                        50 0/6 50.3                                                                   .sup. 66B 25 0/6 62.9                                                         12.5 0/6 53.2                                                                 6.3 0/6 33.7                                                                  .sup. 65B 100 0/6 55.0                                                        .sup. 67B 100 0/6 65.9                                                        50 0/6 41.1                                                                   .sup. 68B 50 3/6 80.3                                                         25 0/6 69.7                                                                   12.5 0/6 49.1                                                                 .sup. 69B 100 0/6 37.8                                                        .sup. 74B 100 1/6 84.1                                                        50 0/6 49.9                                                                   .sup. 75A 25 0/6 61.9                                                         12.5 0/6 42.8                                                                 .sup. 75B 50 4/6 77.8                                                         25 0/6 65.1                                                                   12.5 0/6 37.8                                                                 .sup. 77A 100 2/6 67.3                                                        50 0/6 39.1                                                                ______________________________________                                    

We claim:
 1. A compound of formula I or a pharmaceutically acceptable salt thereof, ##STR11## wherein when X is NH, R is (a) hydrogen, (b) --COR₁ wherein R₁ is (i) a C₁ -C₆ alkyl group which may be substituted by 1-3 substituents selected from halogen, hydroxy, formyloxy, azido, carboxyl, heteroaryl or acetamide, (ii) a C₂ -C₄ alkenyl group, (iii) a C₂ -C₄ alkynyl group, (iv) a C₃ -C₆ cycloalkyl group, (v) a phenyl group which may be substituted by 1-3 substituents selected from hydroxy, halogen, C₁ -C₆ alkoxy group or cyano, (vi) a heteroaryl group having 5-6 ring atoms of which 1-3 atoms are heteroatoms selected from the group consisting of nitrogen and sulfur, (vii) a NR₂ R₃ group wherein R₂ and R₃ are the same or different and each is a hydrogen, C₁ -C₆ alkyl group or (7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl)methyl group or (viii) benzyloxy group;(c) --SO₂ R₄ wherein R₄ is a C₁ -C₆ alkyl group or a phenyl group which may be substituted by 1-3 substituents selected from C₁ -C₆ alkyl group, halogen or C₁ -C₆ alkoxy group; or (d) the group remaining after the removal of the hydroxy group from a carboxy group of 1-2 naturally occurring α-amino acids or their optical isomers, wherein the group may be substituted with protective group, and wherein when X is O,R is the group remaining after the removal of the hydroxy group from a carboxy group of 1-2 naturally occurring α-amino acids or their optical isomers, wherein the group may be substituted with protective group.
 2. The compound as set forth in claim 1 wherein X is NH and R is --COR₁ wherein R₁ is C₁ -C₆ alkyl group which may be substituted by 1-3 substituents selected from halogen, hydroxy, formyloxy, azido, carboxy, heteroaryl or acetamido.
 3. The compound as set forth in claim 1 wherein X is NH and R is --COR₁ wherein R₁ is a NR₂ R₃ wherein R₂ and R₃ are the same or different and each is a hydrogen, C₁ -C₆ alkyl group or (7-oxo-1-aza-4-oxabicyclo[3.2.0]hept-3-yl)methyl group.
 4. The compound as set forth in claim 1, wherein X is NH or O and R is the group remaining after the removal of the hydroxy group from a carboxy group of 1-2 naturally occurring α-amino acids or their optical isomers, wherein the group may be substituted with protective group.
 5. The compound as set forth in claim 1 wherein X is NH, having (3R,5R) or (3S,5S) configuration at two asymmetric carbons on 4-oxa-1-azabicyclo[3.2.0]heptan-7-one ring system or the mixture of them.
 6. The compound as set forth in claim 1 wherein X is O, having (3R,5S) or (3S,5R) configuration at two asymmetric carbons on 4-oxa-1-azabiyclo[3.2.0]heptan-7-one ring system or the mixture of them.
 7. A pharmaceutical composition comprising of a compound as set forth in claim 1 and pharmaceutically acceptable carrier.
 8. A process for preparing a compound as set forth in claim 1wherein when X is O,said process comprising reacting a compound having general formula II with substituted carboxylic acid in the presence of a base in a solvent, ##STR12## and wherein when X is NH, said process comprising converting the compound having general formula II to amino by reaction with metal azide followed by reduction in presence of metal catalyst and reacting the resulting amino compound with acid halide, acid anhydride or activated ester in the presence of a base in a solvent, wherein L is an appropriate leaving group.
 9. A method of treating cancer selected from stomach, lung, breast, liver and uterus cancer and leukemia, in a patient in need thereof, the method comprising administering to the patient a cancer treating-effective amount of a compound as set forth in claim
 1. 